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AKIMOTO Seiji
Graduate School of Science / Division of Chemistry
Professor

Researcher basic information

■ Research Keyword
  • photosynthesis
  • laser
■ Research Areas
  • Natural sciences / Bio-, chemical, and soft-matter physics

Research activity information

■ Award
  • Sep. 2019 Organizing committee AOCP2019, Best Poster Award, Modification of excitation energy-transfer processes of the primary symbiotic algae grown under different light qualities
    Y. Ueno, S. Akimoto

  • Jun. 2019 Organizing committee PRS2019, Outstanding Achievement Award, Responses of energy-transfer processes in diatoms to fluctuating light
    M. Tanabe, S. Akimoto

  • May 2019 日本光合成学会, 最優秀ポスター賞, 灰色藻Cyanophora paradoxa の光捕集機能における培養光質と光量の影響
    植野 嘉文, 秋本 誠志

  • Jul. 2017 光合成セミナー運営委員会, 三室賞, ジビニルクロロフィル型シアノバクテリアProchlorococcus の光環境応答
    濵田 文哉, MURAKAMI AKIO, AKIMOTO SEIJI
    Japan society

  • Oct. 2016 分子科学会, 第10回分子科学討論会(神戸)2016 分子科学会優秀ポスター賞, ピコ秒時間分解蛍光分光法によるフィコビリソームから光化学系への励起エネルギー移動過程に関する研究
    植野 嘉文, AKIMOTO SEIJI
    Japan society

  • Jul. 2016 光合成セミナー運営委員会, 光合成セミナー 三室賞, 絶対蛍光強度測定による緑藻Chlamydomonas reinhardtiiにおける光捕集機能変化の解明
    植野 嘉文, AKIMOTO SEIJI
    Japan society

  • Jun. 2016 Organizing Committee PRS2016, Photosynthesis Research for Sustainability 2016 Young talent awards, Excitation energy transfer processes among photosystethic complexes in cyanobacterial cells
    Yoshifumi Ueno, Seiji Akimoto
    International society

■ Paper
  • Yoshifumi Ueno, Ou-Yang Li, Jian-Ren Shen, Tatsuya Tomo, Seiji Akimoto, Ryo Nagao
    Corresponding, American Chemical Society (ACS), Mar. 2025, The Journal of Physical Chemistry B
    [Refereed]
    Scientific journal

  • Zihao Ye, Mina Sawada, Makiko Iwasa, Ryo Moriyama, Debayan Dey, Miyu Furutani, Mitsutoshi Kitao, Toshihiko Hara, Ayumi Tanaka, Junko Kishimoto, Makio Yokono, Seiji Akimoto, Atsushi Takabayashi, Ryouichi Tanaka
    Abstract Overwintering evergreen trees in boreal regions continuously convert absorbed light energy into heat through a process known as sustained thermal dissipation. To better understand this mechanism, this study examined the alterations in the photosynthetic apparatus and transcriptomes of yew (Taxus cuspidata) leaves throughout the year, comparing sun-exposed and shaded leaves. The Y(II) parameter, conventionally used to estimate the quantum yield of photosystem II (PSII), indicated the occurrence of temperature-dependent thermal dissipation during winter. On the other hand, the levels of photosystem subunits, including the D1 subunit of the PSII reaction center, remained relatively stable year-round, indicating that typical photoinhibition is unlikely to occur. Time-resolved chlorophyll fluorescence analysis revealed that heat dissipation at the PSII antenna is prominent in winter. Winter transcriptomes are notably characterized by a predominance of Elip transcripts encoding early light-induced protein (ELIP), which constitute 20% of the total transcripts, as deduced from RNA-seq analysis. Furthermore, ELIP protein concentration increased to nearly half that of the major light-harvesting complexes. The predicted structure of ELIP includes potential chlorophyll a and carotenoid binding sites. These findings, taken together with a previous report showing ELIP capacity for energy dissipation, lead to a re-evaluation of its significant role in sustained thermal dissipation.
    Oxford University Press (OUP), Oct. 2024, Journal of Experimental Botany, 76(2) (2), 513 - 531
    [Refereed]
    Scientific journal

  • Yoshifumi Ueno, Seiji Akimoto
    Last, Springer Science and Business Media LLC, May 2023, Photosynthesis Research, 159(2-3) (2-3), 165 - 175
    [Refereed]
    Scientific journal

  • Ryo Nagao, Koji Kato, Tasuku Hamaguchi, Yoshifumi Ueno, Naoki Tsuboshita, Shota Shimizu, Miyu Furutani, Shigeki Ehira, Yoshiki Nakajima, Keisuke Kawakami, Takehiro Suzuki, Naoshi Dohmae, Seiji Akimoto, Koji Yonekura, Jian-Ren Shen
    Iron-stress-induced-A proteins (IsiAs) are expressed in cyanobacteria under iron-deficient conditions. The cyanobacterium Anabaena sp. PCC 7120 has four isiA genes; however, their binding property and functional roles in PSI are still missing. We analyzed a cryo-electron microscopy structure of a PSI-IsiA supercomplex isolated from Anabaena grown under an iron-deficient condition. The PSI-IsiA structure contains six IsiA subunits associated with the PsaA side of a PSI core monomer. Three of the six IsiA subunits were identified as IsiA1 and IsiA2. The PSI-IsiA structure lacks a PsaL subunit; instead, a C-terminal domain of IsiA2 occupies the position of PsaL, which inhibits the oligomerization of PSI, leading to the formation of a PSI monomer. Furthermore, excitation-energy transfer from IsiAs to PSI appeared with a time constant of 55 ps. These findings provide insights into both the molecular assembly of the Anabaena IsiA family and the functional roles of IsiAs.
    Corresponding, Feb. 2023, Nature communications, 14(1) (1), 920 - 920, English, International magazine
    Scientific journal
    Link to Kobe Univ. Repository (Kernel)

  • Ryo Nagao, Yoshifumi Ueno, Miyu Furutani, Koji Kato, Jian-Ren Shen, Seiji Akimoto
    Light-harvesting complexes (LHCs) have been diversified in oxygenic photosynthetic organisms, and play an essential role in capturing light energy which is transferred to two types of photosystem cores to promote charge-separation reactions. Red algae are one of the groups of photosynthetic eukaryotes, and their chlorophyll (Chl) a-binding LHCs are specifically associated with photosystem I (PSI). In this study, we purified three types of preparations, PSI-LHCI supercomplexes, PSI cores, and isolated LHCIs, from the red alga Cyanidium caldarium, and examined their properties. The polypeptide bands of PSI-LHCI showed characteristic PSI and LHCI components without contamination by other proteins. The carotenoid composition of LHCI displayed zeaxanthins, β-cryptoxanthins, and β-carotenes. Among the carotenoids, zeaxanthins were enriched in LHCI. On the contrary, both zeaxanthins and β-cryptoxanthins could not be detected from PSI, suggesting that zeaxanthins and β-cryptoxanthins are bound to LHCI but not PSI. A Qy peak of Chl a in the absorption spectrum of LHCI was shifted to a shorter wavelength than those in PSI and PSI-LHCI. This tendency is in line with the result of fluorescence-emission spectra, in which the emission maxima of PSI-LHCI, PSI, and LHCI appeared at 727, 719, and 677 nm, respectively. Time-resolved fluorescence spectra of LHCI represented no 719 and 727-nm fluorescence bands from picoseconds to nanoseconds. These results indicate that energy levels of Chls around/within LHCIs and within PSI are changed by binding LHCIs to PSI. Based on these findings, we discuss the expression, function, and structure of red algal PSI-LHCI supercomplexes.
    Feb. 2023, Photosynthesis research, English, International magazine
    Scientific journal

  • Helena Sapeta, Makio Yokono, Atsushi Takabayashi, Yoshifumi Ueno, André M Cordeiro, Toshihiko Hara, Ayumi Tanaka, Seiji Akimoto, M Margarida Oliveira, Ryouichi Tanaka
    Jatropha curcas is a drought-tolerant plant that maintains its photosynthetic pigments under prolonged drought, and quickly regains its photosynthetic capacity when water is available. It has been reported that drought stress leads to increased thermal dissipation in PSII, but that of PSI has been barely investigated, perhaps due to technical limitations in measuring the PSI absolute quantum yield. In this study, we combined biochemical analysis and spectroscopic measurements using an integrating sphere, and verified that the quantum yields of both photosystems are temporarily down-regulated under drought. We found that the decrease in the quantum yield of PSII was accompanied by a decrease in the core complexes of PSII while light-harvesting complexes are maintained under drought. In addition, in drought-treated plants, we observed a decrease in the absolute quantum yield of PSI as compared with the well-watered control, while the amount of PSI did not change, indicating that non-photochemical quenching occurs in PSI. The down-regulation of both photosystems was quickly lifted in a few days upon re-watering. Our results indicate, that in J. curcas under drought, the down-regulation of both PSII and PSI quantum yield protects the photosynthetic machinery from uncontrolled photodamage.
    Jan. 2023, Journal of experimental botany, 74(1) (1), 336 - 351, English, International magazine
    Scientific journal

  • Kohei Kagatani, Ryo Nagao, Jian-Ren Shen, Yumiko Yamano, Shinichi Takaichi, Seiji Akimoto
    Corresponding, Springer Science and Business Media LLC, Aug. 2022, Photosynthesis Research
    Scientific journal

  • Ryutaro Tokutsu, Eunchul Kim, Seiji Akimoto, Makio Yokono, Konomi Fujimura-Kamada, Norikazu Ohnishi, Yoshifumi Ueno, Jun Minagawa
    Abstract Land plants and microalgae convert solar energy into electrochemical energy by using cooperative two photosystems (PSI and PSII). To maintain optimal photosynthetic rates under variable light conditions in nature, phosphorylation of light-harvesting complex for PSII (LHCII) balances the excitation energy distribution between the two photosystems. Here, we investigated the mechanism of this balancing in a green alga. We show that phospho-LHCIIs physically bind to both photosystems. The energy transfer from the LHCIIs to the PSII core complexes becomes less efficient, whereas the excitation level of PSI increases. The time-resolved fluorescence spectra showed an increase in delayed PSI fluorescence, which represents energetical spillover from PSII to PSI. In addition, the spillover is likely mediated by phospho-LHCIIs and PSI antennas. We hypothesize that the spillover explains the larger extent of phospho-LHCIIs dependent energy balancing in the green alga than land plants, which is important for the short-term photoadaptaion in the algal habitat.
    Cold Spring Harbor Laboratory, Jul. 2022

  • Koji Kato, Tasuku Hamaguchi, Ryo Nagao, Keisuke Kawakami, Yoshifumi Ueno, Takehiro Suzuki, Hiroko Uchida, Akio Murakami, Yoshiki Nakajima, Makio Yokono, Seiji Akimoto, Naoshi Dohmae, Koji Yonekura, Jian-Ren Shen
    Photosystem I (PSI) is a multi-subunit pigment-protein complex that functions in light-harvesting and photochemical charge-separation reactions, followed by reduction of NADP to NADPH required for CO2 fixation in photosynthetic organisms. PSI from different photosynthetic organisms has a variety of chlorophylls (Chls), some of which are at lower-energy levels than its reaction center P700, a special pair of Chls, and are called low-energy Chls. However, the sites of low-energy Chls are still under debate. Here, we solved a 2.04-Å resolution structure of a PSI trimer by cryo-electron microscopy from a primordial cyanobacterium Gloeobacter violaceus PCC 7421, which has no low-energy Chls. The structure shows the absence of some subunits commonly found in other cyanobacteria, confirming the primordial nature of this cyanobacterium. Comparison with the known structures of PSI from other cyanobacteria and eukaryotic organisms reveals that one dimeric and one trimeric Chls are lacking in the Gloeobacter PSI. The dimeric and trimeric Chls are named Low1 and Low2, respectively. Low2 is missing in some cyanobacterial and eukaryotic PSIs, whereas Low1 is absent only in Gloeobacter. These findings provide insights into not only the identity of low-energy Chls in PSI, but also the evolutionary changes of low-energy Chls in oxyphototrophs.
    eLife Sciences Publications, Ltd, Apr. 2022, eLife, 11
    Scientific journal

  • Ryo Nagao, Koji Kato, Minoru Kumazawa, Kentaro Ifuku, Makio Yokono, Takehiro Suzuki, Naoshi Dohmae, Fusamichi Akita, Seiji Akimoto, Naoyuki Miyazaki, Jian-Ren Shen
    Abstract Fucoxanthin chlorophyll (Chl) a/c-binding proteins (FCPs) function as light harvesters in diatoms. The structure of a diatom photosystem II-FCPII (PSII-FCPII) supercomplex have been solved by cryo-electron microscopy (cryo-EM) previously; however, the FCPII subunits that constitute the FCPII tetramers and monomers are not identified individually due to their low resolutions. Here, we report a 2.5 Å resolution structure of the PSII-FCPII supercomplex using cryo-EM. Two types of tetrameric FCPs, S-tetramer, and M-tetramer, are identified as different types of hetero-tetrameric complexes. In addition, three FCP monomers, m1, m2, and m3, are assigned to different gene products of FCP. The present structure also identifies the positions of most Chls c and diadinoxanthins, which form a complicated pigment network. Excitation-energy transfer from FCPII to PSII is revealed by time-resolved fluorescence spectroscopy. These structural and spectroscopic findings provide insights into an assembly model of FCPII and its excitation-energy transfer and quenching processes.
    Corresponding, Springer Science and Business Media LLC, Apr. 2022, Nature Communications, 13(1) (1), 1764 - 1764, English, International magazine
    [Refereed]
    Scientific journal
    Link to Kobe Univ. Repository (Kernel)

  • Hanaki Maeda, Koharu Takahashi, Yoshifumi Ueno, Kei Sakata, Akari Yokoyama, Kozue Yarimizu, Fumiyoshi Myouga, Kazuo Shinozaki, Shin-Ichiro Ozawa, Yuichiro Takahashi, Ayumi Tanaka, Hisashi Ito, Seiji Akimoto, Atsushi Takabayashi, Ryouichi Tanaka
    Springer Science and Business Media LLC, Mar. 2022, Journal of Plant Research, 135(2) (2), 361 - 376
    [Refereed]
    Scientific journal

  • Koji Kato, Ryo Nagao, Yoshifumi Ueno, Makio Yokono, Takehiro Suzuki, Tian-Yi Jiang, Naoshi Dohmae, Fusamichi Akita, Seiji Akimoto, Naoyuki Miyazaki, Jian-Ren Shen
    Abstract Photosystem I (PSI) is one of the two photosystems functioning in light-energy harvesting, transfer, and electron transfer in photosynthesis. However, the oligomerization state of PSI is variable among photosynthetic organisms. We present a 3.8-Å resolution cryo-electron microscopic structure of tetrameric PSI isolated from the glaucophyte alga Cyanophora paradoxa, which reveals differences with PSI from other organisms in subunit composition and organization. The PSI tetramer is organized in a dimer of dimers with a C2 symmetry. Unlike cyanobacterial PSI tetramers, two of the four monomers are rotated around 90°, resulting in a completely different pattern of monomer-monomer interactions. Excitation-energy transfer among chlorophylls differs significantly between Cyanophora and cyanobacterial PSI tetramers. These structural and spectroscopic features reveal characteristic interactions and excitation-energy transfer in the Cyanophora PSI tetramer, suggesting that the Cyanophora PSI could represent a turning point in the evolution of PSI from prokaryotes to eukaryotes.
    Springer Science and Business Media LLC, Mar. 2022, Nature Communications, 13(1) (1), 1679 - 1679, English, International magazine
    Scientific journal

  • Ryo Nagao, Makio Yokono, Yoshifumi Ueno, Yoshiki Nakajima, Takehiro Suzuki, Ka-Ho Kato, Naoki Tsuboshita, Naoshi Dohmae, Jian-Ren Shen, Shigeki Ehira, Seiji Akimoto
    Heterocysts are formed in filamentous heterocystous cyanobacteria under nitrogen-starvation conditions, and possess a very low amount of photosystem II (PSII) complexes than vegetative cells. Molecular, morphological, and biochemical characterizations of heterocysts have been investigated; however, excitation-energy dynamics in heterocysts are still unknown. In this study, we examined excitation-energy-relaxation processes of pigment-protein complexes in heterocysts isolated from the cyanobacterium Anabaena sp. PCC 7120. Thylakoid membranes from the heterocysts showed no oxygen-evolving activity under our experimental conditions and no thermoluminescence-glow curve originating from charge recombination of S2QA-. Two dimensional blue-native/SDS-PAGE analysis exhibits tetrameric, dimeric, and monomeric photosystem I (PSI) complexes but almost no dimeric and monomeric PSII complexes in the heterocyst thylakoids. The steady-state fluorescence spectrum of the heterocyst thylakoids at 77 K displays both characteristic PSI fluorescence and unusual PSII fluorescence different from the fluorescence of PSII dimer and monomer complexes. Time-resolved fluorescence spectra at 77 K, followed by fluorescence decay-associated spectra, showed different PSII and PSI fluorescence bands between heterocysts and vegetative thylakoids. Based on these findings, we discuss excitation-energy-transfer mechanisms in the heterocysts.
    Elsevier BV, Nov. 2021, Biochimica et Biophysica Acta (BBA) - Bioenergetics, 1863(1) (1), 148509 - 148509, English, International magazine
    Scientific journal

  • Yukihiro Kimura, Shingo Nojima, Kazuna Nakata, Takuya Yamashita, Xiang-Ping Wang, Shinji Takenaka, Seiji Akimoto, Masayuki Kobayashi, Michael T. Madigan, Zheng-Yu Wang-Otomo, Long-Jiang Yu
    Nov. 2021, Biochimica et Biophysica Acta (BBA) - Bioenergetics, 1862(11) (11), 148473 - 148473, English
    [Refereed]
    Scientific journal

  • Koji Kato, Tasuku Hamaguchi, Ryo Nagao, Keisuke Kawakami, Yoshifumi Ueno, Takehiro Suzuki, Hiroko Uchida, Akio Murakami, Yoshiki Nakajima, Makio Yokono, Seiji Akimoto, Naoshi Dohmae, Koji Yonekura, Jian-Ren Shen
    AbstractPhotosystem I (PSI) of photosynthetic organisms is a multi-subunit pigment-protein complex and functions in light harvesting and photochemical charge-separation reactions, followed by reduction of NADP to NADPH required for CO2 fixation. PSI from different photosynthetic organisms has a variety of chlorophylls (Chls), some of which are at lower-energy levels than its reaction center P700, a special pair of Chls, and are called low-energy Chls. However, the site of low-energy Chls is still under debate. Here, we solved a 2.04-Å resolution structure of a PSI trimer by cryo-electron microscopy from a primitive cyanobacterium Gloeobacter violaceus PCC 7421, which has no low-energy Chls. The structure showed absence of some subunits commonly found in other cyanobacteria, confirming the primitive nature of this cyanobacterium. Comparison with the known structures of PSI from other cyanobacteria and eukaryotic organisms reveals that one dimeric and one trimeric Chls are lacking in the Gloeobacter PSI. The dimeric and trimeric Chls are named Low1 and Low2, respectively. Low2 does not exist in some cyanobacterial and eukaryotic PSIs, whereas Low1 is absent only in Gloeobacter. Since Gloeobacter is susceptible to light, this indicates that Low1 serves as a main photoprotection site in most oxyphototrophs, whereas Low2 is involved in either energy transfer or energy quenching in some of the oxyphototrophs. Thus, these findings provide insights into not only the functional significance of low-energy Chls in PSI, but also the evolutionary changes of low-energy Chls responsible for the photoprotection machinery from photosynthetic prokaryotes to eukaryotes.
    Cold Spring Harbor Laboratory, Oct. 2021

  • Masakazu Toyoshima, Masumi Sakata, Yoshifumi Ueno, Yoshihiro Toya, Fumio Matsuda, Seiji Akimoto, Hiroshi Shimizu
    In cyanobacteria, it is known that the excitation ratios of photosystem (PS) I and PSII changes with the wavelength of irradiated light due to mobile phycobilisome (PBS) and spillover, affecting the photosynthetic ATP/NADPH synthesis ratio and metabolic flux state. However, the mechanisms by which these changes are controlled have not been well studied. In this study, we performed a targeted proteomic analysis of Synechocystis sp. PCC 6803 under different spectral light conditions to clarify the regulation mechanisms of mobile PBS, spillover and metabolisms under different light qualities at the protein level. The results showed an increase in the amount of proteins mainly involved in CO2 fixation under Red1 light conditions with a high specific growth rate, suggesting that the rate of intracellular metabolism is controlled by the rate of carbon uptake, not by changes in the amount of each enzyme. Correlation analysis between protein levels and PSI/PSII excitation ratios revealed that PsbQUY showed high correlations and significantly increased under Blue and Red2 light conditions, where the PSI/PSII excitation ratio was higher due to spillover. In the strains lacking the genes encoding these proteins, a decrease in the PSI/PSII excitation ratio was observed, suggesting that PsbQUY contribute to spillover occurrence. SIGNIFICANCE: In cyanobacteria, the photosynthetic apparatus's responses, such as state transition [mobile PBS and spillover], occur due to the intensity and wavelength of irradiated light, resulting in changes in photosynthetic electron transport and metabolic flux states. Previous studies have analyzed the response of Synechocystis sp. PCC 6803 to light intensity from various directions, but only spectroscopic analysis of the photosynthetic apparatus has been done on the response to changes in the wavelength of irradiated light. This study analyzed the response mechanisms of mobile PBS, spillover, photosynthetic, and metabolic systems in Synechocystis sp. PCC 6803 under six different spectral light conditions by a targeted proteomic analysis. As a result, many proteins were successfully quantified, and the metabolic enzymes and photosynthetic apparatus were analyzed using an integrated approach. Principal component and correlation analyses and volcano plots revealed that the PSII subunits PsbQ, PsbU, and PsbY have a strong correlation with the PSI/PSII excitation ratio and contribute to spillover occurrence. Thus, statistical analysis based on proteome data revealed that PsbQ, PsbU, and PsbY are involved in spillover, as revealed by spectroscopic analysis.
    Elsevier BV, Aug. 2021, Journal of Proteomics, 246, 104306 - 104306, English, International magazine
    [Refereed]
    Scientific journal

  • Ryo Nagao, Makio Yokono, Ka-Ho Kato, Yoshifumi Ueno, Jian-Ren Shen, Seiji Akimoto
    Photosynthetic organisms finely tune their photosynthetic machinery including pigment compositions and antenna systems to adapt to various light environments. However, it is poorly understood how the photosynthetic machinery in the green flagellate Euglena gracilis is modified under high-light conditions. In this study, we examined high-light modification of excitation-energy-relaxation processes in Euglena cells. Oxygen-evolving activity in the cells incubated at 300 µmol photons m-2 s-1 (HL cells) cannot be detected, reflecting severe photodamage to photosystem II (PSII) in vivo. Pigment compositions in the HL cells showed relative increases in 9'-cis-neoxanthin, diadinoxanthin, and chlorophyll b compared with the cells incubated at 30 µmol photons m-2 s-1 (LL cells). Absolute fluorescence spectra at 77 K exhibit smaller intensities of the PSII and photosystem I (PSI) fluorescence in the HL cells than in the LL cells. Absolute fluorescence decay-associated spectra at 77 K of the HL cells indicate suppression of excitation-energy transfer from light-harvesting complexes (LHCs) to both PSI and PSII with the time constant of 40 ps. Rapid energy quenching in LHCs and PSII in the HL cells is distinctly observed by averaged Chl-fluorescence lifetimes. These findings suggest that Euglena modifies excitation-energy-relaxation processes in addition to pigment compositions to deal with excess energy. These results provide insights into the photoprotection strategies of this alga under high-light conditions.
    Springer Science and Business Media LLC, May 2021, Photosynthesis Research, 149(3) (3), 303 - 311, English, International magazine
    [Refereed]
    Scientific journal

  • Katsunori Yoshikawa, Kenichi Ogawa, Yoshihiro Toya, Seiji Akimoto, Fumio Matsuda, Hiroshi Shimizu
    AbstractIncreased tolerance to light stress in cyanobacteria is a desirable feature for their applications. Here, we obtained a high light tolerant (Tol) strain of Synechocystis sp. PCC6803 through an adaptive laboratory evolution, in which the cells were repeatedly sub-cultured for 52 days under high light stress conditions (7000 to 9000 μmol m−2 s−1). Although the growth of the parental strain almost stopped when exposed to 9000 μmol m−2 s−1, no growth inhibition was observed in the Tol strain. Excitation-energy flow was affected because of photosystem II damage in the parental strain under high light conditions, whereas the damage was alleviated and normal energy flow was maintained in the Tol strain. The transcriptome data indicated an increase in isiA expression in the Tol strain under high light conditions. Whole genome sequence analysis and reverse engineering revealed two mutations in hik26 and slr1916 involved in high light stress tolerance in the Tol strain.
    Springer Science and Business Media LLC, Mar. 2021, Communications Biology, 4(1) (1), 343 - 343, English, International magazine
    [Refereed]
    Scientific journal
    Link to Kobe Univ. Repository (Kernel)

  • Masakazu Toyoshima, Chiaki Yamamoto, Yoshifumi Ueno, Yoshihiro Toya, Seiji Akimoto, Hiroshi Shimizu
    Cyanobacterial type I NADH dehydrogenase (NDH-1) is involved in various bioenergetic reactions including respiration, cyclic electron transport (CET), and CO2 uptake. The role of NDH-1 is usually minor under normal growth conditions and becomes important under stress conditions. However, in our previous study, flux balance analysis (FBA) simulation predicted that the drive of NDH-1 as CET pathway with a photosystem (PS) I/PSII excitation ratio around 1.0 contributes to achieving an optimal specific growth rate. In this study, to experimentally elucidate the predicted functions of NDH-1, first, we measured the PSI/PSII excitation ratios of Synechocystis sp. PCC 6803 grown under four types of spectral light conditions. The specific growth rate was the highest and PSI/PSII excitation ratio was with 0.88 under the single-peak light at 630 nm (Red1). Considering this measured excitation ratios, FBA simulation predicted that NDH-1-dependent electron transport was the major pathway under Red1. Moreover, in actual culture, an NDH-1 deletion strain had slower growth rate than that of wild type only under Red1 light condition. Therefore, we experimentally demonstrated that NDH-1 plays an important role under optimal light conditions such as Red1 light, where Synechocystis exhibits the highest specific growth rate and PSI/PSII excitation ratio of around 1.0.
    Elsevier BV, Mar. 2021, Plant Science, 304, 110798 - 110798, English, International magazine
    [Refereed]
    Scientific journal

  • Ryo Nagao, Makio Yokono, Yoshifumi Ueno, Takehiro Suzuki, Minoru Kumazawa, Ka-Ho Kato, Naoki Tsuboshita, Naoshi Dohmae, Kentaro Ifuku, Jian-Ren Shen, Seiji Akimoto
    Photosynthetic organisms regulate pigment composition and molecular oligomerization of light-harvesting complexes in response to solar light intensities, in order to improve light-harvesting efficiency. Here we report excitation-energy dynamics and relaxation of fucoxanthin chlorophyll a/c-binding protein (FCP) complexes isolated from a diatom Phaeodactylum tricornutum grown under high-light (HL) illumination. Two types of FCP complexes were prepared from this diatom under the HL condition, whereas one FCP complex was isolated from the cells grown under a low-light (LL) condition. The subunit composition and oligomeric states of FCP complexes under the HL condition are different from those under the LL condition. Absorption and fluorescence spectra at 77 K of the FCP complexes also vary between the two conditions, indicating modifications of the pigment composition and arrangement upon the HL illumination. Time-resolved fluorescence curves at 77 K of the FCP complexes under the HL condition showed shorter lifetime components compared with the LL condition. Fluorescence decay-associated spectra at 77 K showed distinct excitation-energy-quenching components and alterations of energy-transfer pathways in the FCP complexes under the HL condition. These findings provide insights into molecular and functional mechanisms of the dynamic regulation of FCPs in this diatom under excess-light conditions.
    Elsevier BV, Feb. 2021, Biochimica et Biophysica Acta (BBA) - Bioenergetics, 1862(2) (2), 148350 - 148350, English, International magazine
    [Refereed]
    Scientific journal

  • Makio Yokono, Yoshifumi Ueno, Seiji Akimoto
    Springer International Publishing, 2021, Photosynthesis: Molecular Approaches to Solar Energy Conversion, 277 - 302
    In book

  • Ryo Nagao, Makio Yokono, Yoshifumi Ueno, Ka-Ho Kato, Naoki Tsuboshita, Jian-Ren Shen, Seiji Akimoto
    Photosynthetic organisms have diversified light-harvesting complexes (LHCs) to collect solar energy efficiently, leading to an acquisition of their ecological niches. Herein we report on biochemical and spectroscopic characterizations of fucoxanthin chlorophyll a/c-binding protein (FCP) complexes isolated from a marine pinguiophyte Glossomastix chrysoplasta. The pinguiophyte FCP showed one subunit band in SDS-PAGE and one protein-complex band with a molecular weight at around 66 kDa in clear-native PAGE. By HPLC analysis, the FCP possesses chlorophylls a and c, fucoxanthin, and violaxanthin. To clarify excitation-energy-relaxation processes in the FCP, we measured time-resolved fluorescence spectra at 77 K of the FCP adapted to pH 5.0, 6.5, and 8.0. Fluorescence curves measured at pH 5.0 and 8.0 showed shorter lifetime components compared with those at pH 6.5. The rapid decay components at pH 5.0 and 8.0 are unveiled by fluorescence decay-associated (FDA) spectra; fluorescence decays occur in the 270 and 160-ps FDA spectra only at pH 5.0 and 8.0, respectively. In addition, energy-transfer pathways with time constants of tens of picoseconds are altered under the basic pH condition but not the acidic pH condition. These findings provide novel insights into pH-dependent energy-transfer and energy-quenching machinery in not only FCP family but also photosynthetic LHCs.
    Corresponding, Elsevier BV, Jan. 2021, Biochimica et Biophysica Acta (BBA) - Bioenergetics, 1862(1) (1), 148306 - 148306, English, International magazine
    [Refereed]
    Scientific journal

  • Ryo Nagao, Makio Yokono, Yoshifumi Ueno, Takehiro Suzuki, Koji Kato, Ka-Ho Kato, Naoki Tsuboshita, Tian-Yi Jiang, Naoshi Dohmae, Jian-Ren Shen, Shigeki Ehira, Seiji Akimoto
    Iron-stress-induced-A proteins (IsiAs) are expressed in cyanobacteria under iron-deficient conditions, and surround photosystem I (PSI) trimer with a ring formation. A cyanobacterium Anabaena sp. PCC 7120 has four isiA genes; however, it is unknown how the IsiAs are associated with PSI. Here we report on molecular organizations and function of the IsiAs in this cyanobacterium. A deletion mutant of the isiA1 gene was constructed, and the four types of thylakoids were prepared from the wild-type (WT) and ΔisiA1 cells under iron-replete (+Fe) and iron-deficient (-Fe) conditions. Immunoblotting analysis exhibits a clear expression of the IsiA1 in the WT-Fe. The PSI-IsiA1 supercomplex is found in the WT-Fe, and excitation-energy transfer from IsiA1 to PSI is verified by time-resolved fluorescence analyses. Instead of the IsiA1, both IsiA2 and IsiA3 are bound to PSI monomer in the ΔisiA1-Fe. These findings provide insights into multiple-expression system of the IsiA family in this cyanobacterium.
    Elsevier BV, Jan. 2021, Biochimica et Biophysica Acta (BBA) - Bioenergetics, 1862(1) (1), 148327 - 148327, English, International magazine
    [Refereed]
    Scientific journal

  • Ryo Nagao, Makio Yokono, Yoshifumi Ueno, Jian-Ren Shen, Seiji Akimoto
    Nov. 2020, The journal of physical chemistry. B, 124(46) (46), 10588 - 10589, English, International magazine
    Scientific journal

  • Chiaki Yamamoto, Masakazu Toyoshima, Sayaka Kitamura, Yoshifumi Ueno, Seiji Akimoto, Yoshihiro Toya, Hiroshi Shimizu
    Photosynthetic organisms produce ATP and NADPH using light as an energy source and further utilize these cofactors during metabolism. Photosynthesis involves linear and cyclic electron flows; as the cyclic electron flow produces ATP more effectively than the linear electron flow without NADPH, the cell efficiently adjusts ATP and NADPH production using the two different pathways. Nevertheless, direct measurement of ATP and NADPH production during photosynthesis has been difficult. In the present study, the photosynthetic ATP and NADPH production rates of Synechocystis sp. PCC 6803 under three different single peak wavelength lights (blue: 470 nm, R630: 630 nm, and R680: 680 nm) were evaluated based on 13C-metabolic flux analysis (13C-MFA) by considering the mass balance of ATP and NADPH between photosynthesis and metabolism. The ratios of ATP/NADPH production via photosynthesis were estimated as 3.13, 1.70, and 2.10 under blue, R630, and R680 light conditions, respectively. Moreover, the linear and cyclic electron flow ratios were estimated to be 1.1-2.2, 0.2-0.5, and 0.5-1.0 under blue, R630, and R680 light conditions, respectively. The predicted linear and cyclic electron flow ratios were consistent with the excitation ratio between photosystems I and II, as observed in the steady-state fluorescence spectra.
    Elsevier BV, Nov. 2020, Journal of Bioscience and Bioengineering, 131(3) (3), 277 - 282, English, Domestic magazine
    [Refereed]
    Scientific journal

  • Ryo Nagao, Makio Yokono, Yoshifumi Ueno, Jian-Ren Shen, Seiji Akimoto
    pH influences excitation-energy-relaxation processes in photosynthetic light-harvesting complexes. Here, we report the excitation-energy dynamics by pH changes in fucoxanthin chlorophyll a/c-binding proteins (FCPs) isolated from a diatom Phaeodactylum tricornutum, probed by time-resolved fluorescence spectroscopy at 77 K. The fluorescence curve measured at pH 5.0 showed a shorter lifetime component than that measured at pH 6.5 and 8.0. The rapid decay component at pH 5.0 is supported by fluorescence decay-associated (FDA) spectra, where strong fluorescence decays relative to fluorescence rises appear in the pH-5.0 FDA spectrum with 70 ps. These results indicate that the diatom FCPs switch their function from light-harvesting to energy-quenching via arrangements of the energy-transfer pathways under acidic pHs. Based on the crystal structure of the diatom FCPs, we propose a model for the energy-quenching machinery through structural changes of the pigment environments, thus providing insights into the pH-dependent light-harvesting strategy in the diatom FCPs.
    Jun. 2020, The journal of physical chemistry. B, 124(24) (24), 4919 - 4923, English, International magazine
    [Refereed]
    Scientific journal

  • Yoshifumi Ueno, Ginga Shimakawa, Shimpei Aikawa, Chikahiro Miyake, Seiji Akimoto
    Oxygenic photosynthesis converts light energy into chemical energy via electron transport and assimilates CO2 in the Calvin-Benson cycle with the chemical energy. Thus, high light and low CO2 conditions induce the accumulation of electrons in the photosynthetic electron transport system, resulting in the formation of reactive oxygen species. To prevent the accumulation of electrons, oxygenic photosynthetic organisms have developed photoprotection mechanisms, including non-photochemical quenching (NPQ) and alternative electron flow (AEF). There are diverse molecular mechanisms underlying NPQ and AEF, and the corresponding molecular actors have been identified and characterized using a model green alga Chlamydomonas reinhardtii. In contrast, detailed information about the photoprotection mechanisms is lacking for other green algal species. In the current study, we examined the photoprotection mechanisms responsive to CO2 in the green alga Chlorella variabilis by combining the analyses of pulse-amplitude-modulated fluorescence, O2 evolution, and the steady-state and time-resolved fluorescence spectra. Under the CO2-limited condition, ΔpH-dependent NPQ occurred in photosystems I and II. Moreover, O2-dependent AEF was also induced. Under the CO2-limited condition with carbon supplementation, NPQ was relaxed and light-harvesting chlorophyll-protein complex II was isolated from both photosystems. In C. variabilis, the O2-dependent AEF and the mechanisms that instantly convert the light-harvesting functions of both photosystems may be important for maintaining efficient photosynthetic activities under various CO2 conditions.
    Jun. 2020, Photosynthesis research, 144(3) (3), 397 - 407, English, International magazine
    [Refereed]
    Scientific journal

  • Ryo Nagao, Koji Kato, Kentaro Ifuku, Takehiro Suzuki, Minoru Kumazawa, Ikuo Uchiyama, Yasuhiro Kashino, Naoshi Dohmae, Seiji Akimoto, Jian-Ren Shen, Naoyuki Miyazaki, Fusamichi Akita
    Photosynthetic light-harvesting complexes (LHCs) play a pivotal role in collecting solar energy for photochemical reactions in photosynthesis. One of the major LHCs are fucoxanthin chlorophyll a/c-binding proteins (FCPs) present in diatoms, a group of organisms having important contribution to the global carbon cycle. Here, we report a 2.40-Å resolution structure of the diatom photosystem I (PSI)-FCPI supercomplex by cryo-electron microscopy. The supercomplex is composed of 16 different FCPI subunits surrounding a monomeric PSI core. Each FCPI subunit showed different protein structures with different pigment contents and binding sites, and they form a complicated pigment-protein network together with the PSI core to harvest and transfer the light energy efficiently. In addition, two unique, previously unidentified subunits were found in the PSI core. The structure provides numerous insights into not only the light-harvesting strategy in diatom PSI-FCPI but also evolutionary dynamics of light harvesters among oxyphototrophs.
    May 2020, Nature communications, 11(1) (1), 2481 - 2481, English, International magazine
    [Refereed]
    Scientific journal
    Link to Kobe Univ. Repository (Kernel)

  • Fusamichi Akita, Ryo Nagao, Koji Kato, Yoshiki Nakajima, Makio Yokono, Yoshifumi Ueno, Takehiro Suzuki, Naoshi Dohmae, Jian-Ren Shen, Seiji Akimoto, Naoyuki Miyazaki
    Iron-stress induced protein A (IsiA) is a chlorophyll-binding membrane-spanning protein in photosynthetic prokaryote cyanobacteria, and is associated with photosystem I (PSI) trimer cores, but its structural and functional significance in light harvesting remains unclear. Here we report a 2.7-Å resolution cryo-electron microscopic structure of a supercomplex between PSI core trimer and IsiA from a thermophilic cyanobacterium Thermosynechococcus vulcanus. The structure showed that 18 IsiA subunits form a closed ring surrounding a PSI trimer core. Detailed arrangement of pigments within the supercomplex, as well as molecular interactions between PSI and IsiA and among IsiAs, were resolved. Time-resolved fluorescence spectra of the PSI-IsiA supercomplex showed clear excitation-energy transfer from IsiA to PSI, strongly indicating that IsiA functions as an energy donor, but not an energy quencher, in the supercomplex. These structural and spectroscopic findings provide important insights into the excitation-energy-transfer and subunit assembly mechanisms in the PSI-IsiA supercomplex.
    May 2020, Communications biology, 3(1) (1), 232 - 232, English, International magazine
    [Refereed]
    Scientific journal
    Link to Kobe Univ. Repository (Kernel)

  • Ryo Nagao, Makio Yokono, Yoshifumi Ueno, Tian-Yi Jiang, Jian-Ren Shen, Seiji Akimoto
    Excitation energy-transfer processes in pigment-protein complexes in photosynthetic organisms are often changed under different pH conditions. However, it is unclear how the pH changes affect excitation energy relaxations in photosystem I (PSI) cores. In this study, we examined the pH sensitivity of energy dynamics in the PSI tetramer, dimer, and monomer isolated from a cyanobacterium, Anabaena sp. PCC 7120, by means of time-resolved fluorescence spectroscopy. Each PSI was adapted to pH 5.0, 6.5, and 8.0. Fluorescence decay-associated (FDA) spectra of the pH 8.0 PSI dimer and monomer showed positive and negative peaks within 5 ps, whereas the FDA spectra of the PSI tetramer did not show such a 5 ps fluorescence component. Mean lifetimes of the fluorescence at pH 6.5 are shorter in the PSI tetramer than in the PSI dimer and monomer, indicating an accelerated energy quenching in the tetramer. The effects of the acidic and basic pHs on the energy-transfer processes differ significantly among the three types of PSIs, suggesting different pH-sensing sites around pigment molecules in the three PSIs. Based on these results, together with our recent structural finding of the PSI tetramer, we discuss functional implications for the pH-sensing regulation of the excitation energy transfer in the PSI tetramer.
    Mar. 2020, The journal of physical chemistry. B, 124(10) (10), 1949 - 1954, English, International magazine
    [Refereed]
    Scientific journal

  • Ryo Nagao, Yoshifumi Ueno, Seiji Akimoto, Jian-Ren Shen
    CO2 concentration and temperature for growth of photosynthetic organisms are two important factors to ensure better photosynthetic performance. In this study, we investigated the effects of CO2 concentration and temperature on the photosynthetic performance in a marine centric diatom Chaetoceros gracilis. Cells were grown under four different conditions, namely, at 25 °C with air bubbling, at 25 °C with a supplementation of 3% CO2, at 30 °C with air bubbling, and at 30 °C with the CO2 supplementation. It was found that the growth rate of cells at 30 °C with the CO2 supplementation is faster than those at other three conditions. The pigment compositions of cells grown under the different conditions are altered, and fluorescence spectra measured at 77 K also showed different peak positions. A novel fucoxanthin chlorophyll a/c-binding protein complex is observed in the cells grown at 30 °C with the CO2 supplementation but not in the other three types of cells. Since oxygen-evolving activities of the four types of cells are almost unchanged, it is suggested that the CO2 supplementation and growth temperature are involved in the regulation of photosynthetic light-harvesting apparatus in C. gracilis at different degrees. Based on these observations, we discuss the favorable growth conditions for C. gracilis.
    Feb. 2020, Photosynthesis research, 146(1-3) (1-3), 189 - 195, English, International magazine
    [Refereed]
    Scientific journal

  • Ryo Nagao, Makio Yokono, Yoshifumi Ueno, Jian-Ren Shen, Seiji Akimoto
    Excitation-energy transfer in photosystem I (PSI) is changed by a cation formation of a special pair chlorophyll P700 in the PSI core; however, it remains unclear how light-harvesting pigment-protein complexes are involved in the P700-related energy-transfer mechanisms. Here, we report effects of the redox changes of P700 on excitation-energy dynamics in diatom PSI-fucoxanthin chlorophyll a/c-binding protein (PSI-FCPI) and PSI core complexes by means of time-resolved fluorescence (TRF) spectroscopy. For the TRF measurements, the PSI-FCPI and PSI were adapted under P700 neutral and cation conditions using chemical reagents. Upon the P700+ formation, fluorescence decay-associated (FDA) spectra constructed from the TRF spectra exhibit a larger fluorescence decay amplitude relative to a fluorescence rise magnitude within 100 ps in each of the PSI-FCPI and PSI. The decay components are shifted to lower wavelengths in each of the P700-cation PSI-FCPI and PSI than in the P700-neutral PSIs. The rapid fluorescence decays upon the P700+ formation are clearly verified by mean lifetimes reconstructed from the FDA spectra. Because the P700-cation PSI does not cause charge-separation reactions, the relatively strong decay components and rapid fluorescence decays observed are likely attributed to excitation-energy quenching. These observations suggest that chlorophylls in PSI and around/within FCPI are involved in the energy-quenching events by the redox changes of P700.
    Feb. 2020, The journal of physical chemistry. B, 124(8) (8), 1481 - 1486, English, International magazine
    [Refereed]
    Scientific journal

  • Miyuki Tanabe, Yoshifumi Ueno, Makio Yokono, Jian-Ren Shen, Ryo Nagao, Seiji Akimoto
    A marine pennate diatom Phaeodactylum tricornutum (Pt) and a marine centric diatom Chaetoceros gracilis (Cg) possess unique light-harvesting complexes, fucoxanthin chlorophyll a/c-binding proteins (FCPs). FCPs have dual functions: light harvesting in the blue to green regions and quenching of excess energy. So far, excitation dynamics including FCPs have been studied by altering continuous light conditions. In the present study, we examined responses of the diatom cells to fluctuating light (FL) conditions. Excitation dynamics in the cells incubated under the FL conditions were analyzed by time-resolved fluorescence measurements followed by global analysis. As responses common to the Pt and Cg cells, quenching behaviors were observed in photosystem (PS) II with time constants of hundreds of picoseconds. The PSII → PSI energy transfer was modified only in the Pt cells, whereas quenching in FCPs was suggested only in the Cg cells, indicating different strategy for the dissipation of excess energy under the FL conditions.
    Feb. 2020, Photosynthesis research, 146(1-3) (1-3), 143 - 150, English, International magazine
    [Refereed]
    Scientific journal

  • Seiji Akimoto, Yoshifumi Ueno, Makio Yokono, Jian-Ren Shen, Ryo Nagao
    Diatoms are a major group of microalgae in marine and freshwater environments. To utilize the light energy in blue to green region, diatoms possess unique antenna pigment-protein complexes, fucoxanthin chlorophyll a/c-binding proteins (FCPs). Depending on light qualities and quantities, diatoms form FCPs with different energies: normal-type and red-shifted FCPs. In the present study, we examined changes in light-harvesting and energy-transfer processes of a diatom Chaetoceros gracilis cells grown using white- and single-colored light-emitting diodes (LEDs), by means of time-resolved fluorescence spectroscopy. The blue LED, which is harvested by FCPs, modified energy transfer involving CP47, and suppressed energy transfer to PSI. Under the red-LED conditions, which is absorbed by both FCPs and PSs, energy transfer to PSI was enhanced, and the red-shifted FCP appeared. The red-shifted FCP was also recognized under the green- and yellow-LEDs, suggesting that lack of the shorter-wavelength light induces the red-shifted FCP. Functions of the red-shifted FCPs are discussed.
    Jan. 2020, Photosynthesis research, 146(1-3) (1-3), 87 - 93, English, International magazine
    [Refereed]
    Scientific journal

  • Kumiko Oka, Yoshifumi Ueno, Makio Yokono, Jian-Ren Shen, Ryo Nagao, Seiji Akimoto
    Fucoxanthin-chlorophyll (Chl) a/c-binding proteins (FCPs) are light-harvesting pigment-protein complexes found in diatoms and brown algae. Due to the characteristic pigments, such as fucoxanthin and Chl c, FCPs can capture light energy in blue-to green regions. A pennate diatom Phaeodactylum tricornutum synthesizes a red-shifted form of FCP under weak or red light, extending a light-absorption ability to longer wavelengths. In the present study, we examined changes in light-harvesting and energy-transfer processes of P. tricornutum cells grown under white- and single-colored light-emitting diodes (LEDs). The red-shifted FCP appears in the cells grown under the green, yellow, and red LEDs, and exhibited a fluorescence peak around 714 nm. Additional energy-transfer pathways are established in the red-shifted FCP; two forms (F713 and F718) of low-energy Chl a work as energy traps at 77 K. Averaged fluorescence lifetimes are prolonged in the cells grown under the yellow and red LEDs, whereas they are shortened in the blue-LED-grown cells. Based on these results, we discussed the light-adaptation machinery of P. tricornutum cells involved in the red-shifted FCP.
    Jan. 2020, Photosynthesis research, 146(1-3) (1-3), 227 - 234, English, International magazine
    [Refereed]
    Scientific journal

  • Koji Kato, Toshiyuki Shinoda, Ryo Nagao, Seiji Akimoto, Takehiro Suzuki, Naoshi Dohmae, Min Chen, Suleyman I Allakhverdiev, Jian-Ren Shen, Fusamichi Akita, Naoyuki Miyazaki, Tatsuya Tomo
    Chlorophylls (Chl) play pivotal roles in energy capture, transfer and charge separation in photosynthesis. Among Chls functioning in oxygenic photosynthesis, Chl f is the most red-shifted type first found in a cyanobacterium Halomicronema hongdechloris. The location and function of Chl f in photosystems are not clear. Here we analyzed the high-resolution structures of photosystem I (PSI) core from H. hongdechloris grown under white or far-red light by cryo-electron microscopy. The structure showed that, far-red PSI binds 83 Chl a and 7 Chl f, and Chl f are associated at the periphery of PSI but not in the electron transfer chain. The appearance of Chl f is well correlated with the expression of PSI genes induced under far-red light. These results indicate that Chl f functions to harvest the far-red light and enhance uphill energy transfer, and changes in the gene sequences are essential for the binding of Chl f.
    Jan. 2020, Nature communications, 11(1) (1), 238 - 238, English, International magazine
    [Refereed]
    Scientific journal
    Link to Kobe Univ. Repository (Kernel)

  • Ryo Furukawa, Michiki Aso, Tomomichi Fujita, Seiji Akimoto, Ryouichi Tanaka, Ayumi Tanaka, Makio Yokono, Atsushi Takabayashi
    Springer Science and Business Media {LLC}, Nov. 2019, Journal of Plant Research, English
    [Refereed]
    Scientific journal

  • Koji Kato, Ryo Nagao, Tian-Yi Jiang, Yoshifumi Ueno, Makio Yokono, Siu Kit Chan, Mai Watanabe, Masahiko Ikeuchi, Jian-Ren Shen, Seiji Akimoto, Naoyuki Miyazaki, Fusamichi Akita
    Photosystem I (PSI) functions to harvest light energy for conversion into chemical energy. The organisation of PSI is variable depending on the species of organism. Here we report the structure of a tetrameric PSI core isolated from a cyanobacterium, Anabaena sp. PCC 7120, analysed by single-particle cryo-electron microscopy (cryo-EM) at 3.3 Å resolution. The PSI tetramer has a C2 symmetry and is organised in a dimer of dimers form. The structure reveals interactions at the dimer-dimer interface and the existence of characteristic pigment orientations and inter-pigment distances within the dimer units that are important for unique excitation energy transfer. In particular, characteristic residues of PsaL are identified to be responsible for the formation of the tetramer. Time-resolved fluorescence analyses showed that the PSI tetramer has an enhanced excitation-energy quenching. These structural and spectroscopic findings provide insights into the physiological significance of the PSI tetramer and evolutionary changes of the PSI organisations.
    Corresponding, Oct. 2019, Nature communications, 10(1) (1), 4929 - 4929, English, International magazine
    [Refereed]
    Scientific journal
    Link to Kobe Univ. Repository (Kernel)

  • Ryo Nagao, Yoshifumi Ueno, Makio Yokono, Jian-Ren Shen, Seiji Akimoto
    Controlling excitation energy flow is a fundamental ability of photosynthetic organisms to keep a better performance of photosynthesis. Among the organisms, diatoms have unique light-harvesting complexes, fucoxanthin chlorophyll (Chl) a/c-binding proteins. We have recently investigated light-adaptation mechanisms of a marine centric diatom, Chaetoceros gracilis, by spectroscopic techniques. However, it remains unclear how pennate diatoms regulate excitation energy under different growth light conditions. Here, we studied light-adaptation mechanisms in a marine pennate diatom Phaeodactylum tricornutum grown at 30 µmol photons m-2 s-1 and further incubated for 24 h either in the dark, or at 30 or 300 µmol photons m-2 s-1 light intensity, by time-resolved fluorescence (TRF) spectroscopy. The high-light incubated cells showed no detectable oxygen-evolving activity of photosystem II, indicating the occurrence of a severe photodamage. The photodamaged cells showed alterations of steady-state absorption and fluorescence spectra and TRF spectra compared with the dark and low-light adapted cells. In particular, excitation-energy quenching is significantly accelerated in the photodamaged cells as shown by mean lifetime analysis of the Chl fluorescence. These spectral changes by the high-light treatment may result from arrangements of pigment-protein complexes to maintain the photosynthetic performance under excess light illumination. These growth-light dependent spectral properties in P. tricornutum are largely different from those in C. gracilis, thus providing insights into the different light-adaptation mechanisms between the pennate and centric diatoms.
    Sep. 2019, Photosynthesis research, 141(3) (3), 355 - 365, English, International magazine
    [Refereed]
    Scientific journal

  • Yoshifumi Ueno, Ryo Nagao, Jian-Ren Shen, Seiji Akimoto
    Fucoxanthin chlorophyll a/c-binding proteins (FCPs) are unique light harvesters for some photosynthetic organisms. There were several reports for the alterations of FCPs in response to light conditions. Here, we present the spectral profiles and excitation dynamics of novel FCP complexes isolated from the diatom Chaetoceros gracilis. Under a red-light condition, C. gracilis cells expressed three types of FCP complexes, two of which are very similar to FCP complexes found in the white-light grown cells, and one of which is the novel FCP complex. The combination of steady-state absorption and fluorescence spectra and time-resolved fluorescence spectra revealed that, compared to other types of FCP complexes, the novel FCP complexes exhibited red-shifted absorption and fluorescence spectra and fast decay of excitation. This finding will provide new insights into not only the light-harvesting strategies of diatoms but also the diversity of light adaptation machinery for photosynthetic organisms.
    Aug. 2019, The journal of physical chemistry letters, 10(17) (17), 5148 - 5152, English, International magazine
    [Refereed]
    Scientific journal

  • Yasunori Matsui, Shuhei Kawaoka, Hiroki Nagashima, Tatsuo Nakagawa, Naoki Okamura, Takuya Ogaki, Eisuke Ohta, Seiji Akimoto, Ayana Sato-Tomita, Shigeyuki Yagi, Yasuhiro Kobori, Hiroshi Ikeda
    Aug. 2019, Journal of Physical Chemistry C, 123(31) (31), 18813 - 18823, English
    [Refereed]
    Scientific journal
    Link to Kobe Univ. Repository (Kernel)

  • Ryo Nagao, Koji Kato, Takehiro Suzuki, Kentaro Ifuku, Ikuo Uchiyama, Yasuhiro Kashino, Naoshi Dohmae, Seiji Akimoto, Jian-Ren Shen, Naoyuki Miyazaki, Fusamichi Akita
    Springer Science and Business Media LLC, Aug. 2019, Nature Plants, 5(8) (8), 890 - 901
    [Refereed]
    Scientific journal

  • Ryo Nagao, Makio Yokono, Yoshifumi Ueno, Jian-Ren Shen, Seiji Akimoto
    Excitation energy-transfer processes in photosynthetic light-harvesting complexes are strongly affected by the surrounding environments of pigments. Here we report on the effects of pH changes on excitation energy dynamics in both diatom photosystem I-fucoxanthin chlorophyll a/ c-binding protein (PSI-FCPI) and PSI core complexes by means of fluorescence spectroscopies. The steady-state fluorescence spectra of the PSI-FCPI showed similar features among three samples at pH 5.0, 6.5, and 8.0. However, fluorescence decay-associated spectra of the pH 5.0- and 8.0-adapted PSI-FCPI within 100 ps exhibit peak shifts to longer and shorter wavelengths, respectively, than the peaks in the pH 6.5 spectra. Because such spectral changes hardly occur in the PSI complexes, the peak shifts at pH 5.0 and 8.0 in the PSI-FCPI can be ascribed to alterations of pigment-pigment and/or pigment-protein interactions around/within FCPI caused by the pH changes. These findings provide novel physical insights into the pH-sensing light-harvesting strategy in diatom PSI-FCPI.
    Jul. 2019, The journal of physical chemistry letters, 10(13) (13), 3531 - 3535, English, International magazine
    [Refereed]
    Scientific journal

  • The PSI-PSII megacomplex in green plants
    Makio Yokono, Atsushi Takabayashi, Junko Kishimoto, Tomomichi Fujita, Masakazu Iwai, MURAKAMI AKIO, Seiji Akimoto, Ayumi Tanaka
    May 2019, Plant and Cell Physiology, English
    [Refereed]
    Scientific journal

  • Ryo Nagao, Yoshifumi Ueno, Fusamichi Akita, Takehiro Suzuki, Naoshi Dohmae, Seiji Akimoto, Jian-Ren Shen
    Diatoms are dominant phytoplankton in aquatic environments and have unique light-harvesting apparatus, fucoxanthin chlorophyll a/c-binding protein (FCP). Diatom photosystem I (PSI) interacts with specific FCPs (FCPI); however, it remains unclear how PSI cores receive excitation energy from FCPI. To analyze the energy transfer dynamics, it is necessary to isolate both PSI cores and PSI-FCPI complexes. In this study, we prepared three PSI complexes, which are PSI-FCPI membrane fragments, detergent-solubilized PSI-FCPI supercomplexes and PSI core-like complexes, from the marine centric diatom, Chaetoceros gracilis, and examined their biochemical properties. Both the PSI-FCPI membrane fragments and supercomplexes showed similar subunit compositions including FCPI, whereas the PSI complexes were devoid of most FCPI subunits. The purity and homogeneity of the two detergent-solubilized PSI preparations were verified by clear-native PAGE and electron microscopy. The difference of pigment contents among the three PSI samples was shown by absorption spectra at 77 K. The intensity in the whole spectrum of PSI-FCPI membranes was much higher than those of the other two complexes, while the spectral shape of PSI complexes was similar to that of cyanobacterial PSI core complexes. 77-K fluorescence spectra of the three PSI preparations exhibited different spectral shapes, especially peak positions and band widths. Based on these observations, we discuss the merits of three PSI preparations for evaluating excitation energy dynamics in diatom PSI-FCPI complexes.
    May 2019, Photosynthesis research, 140(2) (2), 141 - 149, English, International magazine
    [Refereed]
    Scientific journal

  • Hisako Kubota-Kawai, Raymond N Burton-Smith, Ryutaro Tokutsu, Chihong Song, Seiji Akimoto, Makio Yokono, Yoshifumi Ueno, Eunchul Kim, Akimasa Watanabe, Kazuyoshi Murata, Jun Minagawa
    Mar. 2019, The Journal of biological chemistry, 294(12) (12), 4304 - 4314, English, International magazine
    [Refereed]
    Scientific journal

  • Yasunori Matsui, Shuhei Kawaoka, Hiroki Nagashima, Tatsuo Nakagawa, Naoki Okamura, Takuya Ogaki, Eisuke Ohta, Seiji Akimoto, Shigeyuki Yagi, Yasuhiro Kobori, Hiroshi Ikeda
    American Chemical Society ({ACS}), Mar. 2019

  • Regulation of excitation energy in Nannochloropsis photosystem II
    M. Yokono, I. Umetani, A. Takabayashi, AKIMOTO SEIJI, A. Tanaka
    Mar. 2019, Photosynth. Res., 139, 155 - 161, English
    [Refereed]
    Scientific journal

  • Yoshifumi Ueno, Shimpei Aikawa, Akihiko Kondo, Seiji Akimoto
    Oxygenic photosynthetic organisms perform photosynthesis efficiently by distributing captured light energy to photosystems (PSs) at an appropriate balance. Maintaining photosynthetic efficiency under changing light conditions requires modification of light-harvesting and energy-transfer processes. In the current study, we examined how green algae regulate their light-harvesting functions in response to different light qualities. We measured low-temperature time-resolved fluorescence spectra of unicellular green algae Chlamydomonas reinhardtii and Chlorella variabilis cells grown under different light qualities. By observing the delayed fluorescence spectra, we demonstrated that both types of green algae primarily modified the associations between light-harvesting chlorophyll protein complexes (LHCs) and PSs (PSII and PSI). Under blue light, Chlamydomonas transferred more energy from LHC to chlorophyll (Chl) located far from the PSII reaction center, while energy was transferred from LHC to PSI via different energy-transfer pathways in Chlorella. Under green light, both green algae exhibited enhanced energy transfer from LHCs to both PSs. Red light induced fluorescence quenching within PSs in Chlamydomonas and LHCs in Chlorella. In Chlorella, energy transfer from PSII to PSI appears to play an important role in balancing excitation between PSII and PSI.
    Mar. 2019, Photosynthesis research, 139(1-3) (1-3), 145 - 154, English, International magazine
    [Refereed]
    Scientific journal

  • Ultrafast excitation-energy dyamics in diatom photosystem I-antenna complex: a femtosecond fluorescence upconversin study
    R. Nagao, K. Kagatani, Y. Ueno, J.-R. Shen, AKIMOTO SEIJI
    Feb. 2019, J. Phys. Chem. B, 123, 2673 - 2678, English
    [Refereed]
    Scientific journal

  • Ryo Nagao, Makio Yokono, Yoshifumi Ueno, Jian-Ren Shen, Seiji Akimoto
    Photosynthetic organisms handle solar energy precisely to achieve efficient photochemical reactions. Because there are a wide variety of light-harvesting antennas in oxyphototrophs, the excitation energy transfer mechanisms are thought to differ significantly. In this study, we compared excitation energy dynamics between photosystem I (PSI) cores and a complex between PSI and fucoxanthin chlorophyll (Chl) a/ c-binding protein I (PSI-FCPI) isolated from a diatom, Chaetoceros gracilis, by means of picosecond time-resolved fluorescence analyses. Time-resolved spectra measured at 77 K clearly show that low-energy Chls in the FCPI transfer not only most of the excitation energy to the reaction center Chls in the PSI cores but also the remaining energy to carotenoids for quenching. Under room-temperature conditions, the energy in the low-energy Chls is rapidly equilibrated on Chls in the PSI cores by uphill energy transfer within a few tens of picoseconds. These findings provide solid evidence that the low-energy Chls in the FCPI contribute to the photochemical reactions in PSI.
    Jan. 2019, The journal of physical chemistry. B, 123(1) (1), 66 - 70, English, International magazine
    [Refereed]
    Scientific journal

  • Makio Yokono, Seiji Akimoto
    Elsevier Ltd, Dec. 2018, Current Opinion in Biotechnology, 54, 50 - 56, English
    [Refereed][Invited]
    Scientific journal

  • Singlet-Fission-Born Quintet State: Sublevel Selections and Trapping by Multiexciton Thermodynamics
    Hiroki Nagashima, Shuhei Kawaoka, AKIMOTO SEIJI, TACHIKAWA TAKASHI, Yasunori Matsui, Hiroshi Ikeda, KOBORI YASUHIRO
    Sep. 2018, The Journal of Physical Chemistry Letters, 9(19) (19), 5855–5861, English
    [Refereed]
    Scientific journal

  • Ryo Nagao, Yoshifumi Ueno, Makio Yokono, Jian-Ren Shen, Seiji Akimoto
    Maintenance of energy balance under changeable light conditions is an essential function of photosynthetic organisms to achieve efficient photochemical reactions. Among the photosynthetic organisms, diatoms possess light-harvesting fucoxanthin chlorophyll (Chl) a/c-binding protein (FCP) as peripheral antennas. However, how diatoms regulate excitation-energy distribution between FCP and the two photosystem cores during light adaptation is poorly understood. In this study, we examined spectroscopic properties of a marine diatom Chaetoceros gracilis adapted in the dark and at photosynthetic photon flux density at 30 and 300 μmol photons m-2 s-1. Absorption spectra at 77 K showed significant changes in the Soret region, and 77-K steady-state fluorescence spectra showed significant differences in the spectral shape and relative fluorescence intensity originating from both PSII and PSI, among the cells grown under different light conditions. These results suggest alterations of pigment composition and their interactions under the different light conditions. These alterations affected the excitation-energy dynamics monitored by picosecond time-resolved fluorescence analyses at 77 K significantly. The contributions of Chls having lower energy levels than the reaction center Chls in the two photosystems to the energy dynamics were clearly identified in the three cells but with presumably different roles. These findings provide insights into the regulatory mechanism of excitation-energy balance in diatoms under various light conditions.
    Jul. 2018, Biochimica et biophysica acta. Bioenergetics, 1859(7) (7), 524 - 530, English, International magazine
    [Refereed]
    Scientific journal

  • Fumitoshi Ema, Mana Tanabe, Shohei Saito, Tomoki Yoneda, Kenji Sugisaki, Takashi Tachikawa, Seiji Akimoto, Seigo Yamauchi, Kazunobu Sato, Atsuhiro Osuka, Takeji Takui, Yasuhiro Kobori
    Möbius aromatic molecules have attracted great attention as new functional materials because of their π-orbital cyclic conjugations lying along the twisted Möbius topology. To elucidate the electronic character of the lowest excited triplet (T1) state of a Möbius aromatic [28]hexaphyrin, we employed a time-resolved electron paramagnetic resonance (TREPR) method with applied magnetophotoselection measurements at 77 K. Analyses of the EPR parameters have revealed that the T1 state possesses intramolecular charge-transfer (CT) character together with local excitation character residing at one side in the Möbius strip ring. We have also demonstrated that the CT character between orthogonal unpaired orbitals triggers quick triplet deactivation by spin-orbit coupling. This deactivation can be an important barometer to represent the "antiaromaticity" because of a connection between the orthogonal CT character and instability by a weakened spin-spin exchange coupling in the T1 state.
    May 2018, The journal of physical chemistry letters, 9(10) (10), 2685 - 2690, English, International magazine
    [Refereed]
    Scientific journal
    Link to Kobe Univ. Repository (Kernel)

  • Kotaro Kosuge, Ryutaro Tokutsu, Eunchul Kim, Seiji Akimoto, Makio Yokono, Yoshifumi Ueno, Jun Minagawa
    Photosynthetic organisms are frequently exposed to light intensities that surpass the photosynthetic electron transport capacity. Under these conditions, the excess absorbed energy can be transferred from excited chlorophyll in the triplet state (3Chl*) to molecular O2, which leads to the production of harmful reactive oxygen species. To avoid this photooxidative stress, photosynthetic organisms must respond to excess light. In the green alga Chlamydomonas reinhardtii, the fastest response to high light is nonphotochemical quenching, a process that allows safe dissipation of the excess energy as heat. The two proteins, UV-inducible LHCSR1 and blue light-inducible LHCSR3, appear to be responsible for this function. While the LHCSR3 protein has been intensively studied, the role of LHCSR1 has been only partially elucidated. To investigate the molecular functions of LHCSR1 in C. reinhardtii, we performed biochemical and spectroscopic experiments and found that the protein mediates excitation energy transfer from light-harvesting complexes for Photosystem II (LHCII) to Photosystem I (PSI), rather than Photosystem II, at a low pH. This altered excitation transfer allows remarkable fluorescence quenching under high light. Our findings suggest that there is a PSI-dependent photoprotection mechanism that is facilitated by LHCSR1.
    Apr. 2018, Proceedings of the National Academy of Sciences of the United States of America, 115(14) (14), 3722 - 3727, English, International magazine
    [Refereed]
    Scientific journal

  • 緑色植物のPSI-PSII複合体
    横野 牧生, 高林 厚史, 岸本 純子, 藤田 知道, 岩井 優和, MURAKAMI AKIO, AKIMOTO SEIJI, 田中 歩
    Apr. 2018, 光合成研究, 28(1) (1), 15 - 19, Japanese
    [Refereed]
    Scientific journal

  • Light-harvesting strategy during CO2-dependent photosynthesis in the green alga Chlamydomonas reinhardtii
    Y. Ueno, G. Shimakawa, MIYAKE CHIKAHIRO, AKIMOTO SEIJI
    2018, J. Phys. Chem. Lett., 9, 1028 - 1033, English
    [Refereed]
    Scientific journal

  • Y. Kimura, K. Hashimoto, S. Akimoto, M. Takenouchi, K. Suzuki, R. Kishi, M. Imanishi, S. Takenaka, M.T. Madigan, K.V.P. Nagashima, Z.-Y.W.-Otomo
    2018, Biochemistry, in press(30) (30), 4496 - 4503, English
    [Refereed]
    Scientific journal

  • Eunchul Kim, Seiji Akimoto, Ryutaro Tokutsu, Makio Yokono, Jun Minagawa
    Nov. 2017, JOURNAL OF BIOLOGICAL CHEMISTRY, 292(46) (46), 18951 - 18960, English
    [Refereed]
    Scientific journal

  • Yukako Kato, Makio Yokono, Seiji Akimoto, Atsushi Takabayashi, Ayumi Tanaka, Ryouichi Tanaka
    Nov. 2017, PLANT AND CELL PHYSIOLOGY, 58(11) (11), 2026 - 2039, English
    [Refereed]
    Scientific journal

  • Fumiya Hamada, Akio Murakami, Seiji Akimoto
    Oct. 2017, JOURNAL OF PHYSICAL CHEMISTRY B, 121(39) (39), 9081 - 9090, English
    [Refereed]
    Scientific journal

  • Keigo Imamura, Yoshifumi Ueno, Seiji Akimoto, Kazuo Eda, Yanqing Du, Chaolu Eerdun, Meiling Wang, Kumiko Nishinaka, Akihiko Tsuda
    A novel acid-responsive single trichromatic luminescent dye capable of emitting pure white light (WL) is reported. A newly designed p-phenylene-bridged bipyrrole bearing N-alkylimino groups (1 a) specifically provides WL emission upon mixing with trifluoroacetic acid (TFA) in a CH2Cl2 solution. The emission originates from the trichromatic luminescent behavior of 1 a upon protonation of the imino groups. The blue-light-emitting 1 a exhibits dramatic color changes in fluorescence to orange and green upon mono- and diprotonation, respectively, providing a wide emission band in the range of λ=400-800 nm that provide WL when the compound is in a dynamic equilibrium between the three states. The sample also exhibits low self-absorption of the emitted light and a high fluorescence quantum yield upon excitation with UV light.
    Oct. 2017, ChemPhotoChem, 1(10) (10), 427 - 431, English, International magazine
    [Refereed]
    Scientific journal
    Link to Kobe Univ. Repository (Kernel)

  • Aya Onishi, Shimpei Aikawa, Akihiko Kondo, Seiji Akimoto
    Sep. 2017, PHOTOSYNTHESIS RESEARCH, 133(1-3) (1-3), 317 - 326, English
    [Refereed]
    Scientific journal

  • Yoshifumi Ueno, Shimpei Aikawa, Kyosuke Niwa, Tomoko Abe, Akio Murakami, Akihiko Kondo, Seiji Akimoto
    Sep. 2017, PHOTOSYNTHESIS RESEARCH, 133(1-3) (1-3), 235 - 243, English
    [Refereed]
    Scientific journal

  • Seiji Akimoto, Makio Yokono
    Springer International Publishing, May 2017, Photosynthesis: Structures, Mechanisms, and Applications, 169 - 184, English
    [Refereed]
    In book

  • 光化学系I-光化学系II超複合体の発見と機能 新しい光防御機構
    横野 牧生, 高林 厚史, AKIMOTO SEIJI, 田中 歩
    日本農芸化学会 ; 1962-, 2017, 化学と生物, 55(2) (2), 78 - 80, Japanese
    [Refereed]
    Scientific journal

  • Yoko Marutani, Yasuo Yamauchi, Mari Higashiyama, Akihito Miyoshi, Seiji Akimoto, Kanako Inoue, Ken-ichi Ikeda, Masaharu Mizutani, Yukihiro Sugimoto
    Jan. 2017, PHOTOSYNTHESIS RESEARCH, 131(1) (1), 41 - 50, English
    [Refereed]
    Scientific journal

  • Ginga Shimakawa, Seiji Akimoto, Yoshifumi Ueno, Ayumi Wada, Keiichiro Shaku, Yuichiro Takahashi, Chikahiro Miyake
    Dec. 2016, PHOTOSYNTHESIS RESEARCH, 130(1-3) (1-3), 293 - 305, English
    [Refereed]
    Scientific journal

  • Ginga Shimakawa, Seiji Akimoto, Yoshifumi Ueno, Ayumi Wada, Keiichiro Shaku, Yuichiro Takahashi, Chikahiro Miyake
    Dec. 2016, PHOTOSYNTHESIS RESEARCH, 130(1-3) (1-3), 293 - 305, English
    [Refereed]
    Scientific journal

  • Kazunori Tanaka, Satoko Iida, Shinichi Takaichi, Mamoru Mimuro, Akio Murakami, Seiji Akimoto
    Dec. 2016, PHOTOSYNTHESIS RESEARCH, 130(1-3) (1-3), 183 - 191, English
    [Refereed]
    Scientific journal

  • Yoshifumi Ueno, Shimpei Aikawa, Akihiko Kondo, Seiji Akimoto
    Sep. 2016, JOURNAL OF PHYSICAL CHEMISTRY LETTERS, 7(18) (18), 3567 - 3571, English
    [Refereed]
    Scientific journal

  • Fumiya Hamada, Akio Murakami, Seiji Akimoto
    Dec. 2015, JOURNAL OF PHYSICAL CHEMISTRY B, 119(51) (51), 15593 - 15600, English
    [Refereed]
    Scientific journal

  • Makio Yokono, Ryo Nagao, Tatsuya Tomo, Seiji Akimoto
    Oct. 2015, BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS, 1847(10) (10), 1274 - 1282, English
    [Refereed]
    Scientific journal

  • Yoshifumi Ueno, Shimpei Aikawa, Akihiko Kondo, Seiji Akimoto
    Aug. 2015, PHOTOSYNTHESIS RESEARCH, 125(1-2) (1-2), 211 - 218, English
    [Refereed]
    Scientific journal

  • Seiji Akimoto, Toshiyuki Shinoda, Min Chen, Suleyman I. Allakhverdiev, Tatsuya Tomo
    Aug. 2015, PHOTOSYNTHESIS RESEARCH, 125(1-2) (1-2), 115 - 122, English
    [Refereed]
    Scientific journal

  • Aya Onishi, Shimpei Aikawa, Akihiko Kondo, Seiji Akimoto
    Aug. 2015, PHOTOSYNTHESIS RESEARCH, 125(1-2) (1-2), 191 - 199, English
    [Refereed]
    Scientific journal

  • Kenta Niki, Shimpei Aikawa, Makio Yokono, Akihiko Kondo, Seiji Akimoto
    Aug. 2015, PHOTOSYNTHESIS RESEARCH, 125(1-2) (1-2), 201 - 210, English
    [Refereed]
    Scientific journal

  • M. Yokono, A. Takabayashi, S. Akimoto, A. Tanaka
    Mar. 2015, NATURE COMMUNICATIONS, 6, 6675, English
    [Refereed]
    Scientific journal

  • Masakazu Iwai, Makio Yokono, Masaru Kono, Ko Noguchi, Seiji Akimoto, Akihiko Nakano
    Jan. 2015, NATURE PLANTS, 1(2) (2), 14008, English
    [Refereed]
    Scientific journal

  • 新奇クロロフィルを持つシアノバクテリアのエネルギー移動機構の解析
    篠田 稔行, AKIMOTO SEIJI, 二井 大輔, 太田 尚孝, 鞆 達也
    The Japanese Society of Photosynthesis Research, 2015, 光合成研究, 25(1) (1), 28 - 33, Japanese
    [Refereed][Invited]
    Scientific journal

  • クロロフィルの光エネルギー捕集にみられる多様性
    AKIMOTO SEIJI, 鞆 達也
    The Japanese Society of Photosynthesis Research, 2015, 光合成研究, 25(1) (1), 36 - 41, Japanese
    [Refereed][Invited]
    Scientific journal

  • Akimoto S, Teshigahara A, Yokono M, Mimuro M, Nagao R, Tomo T
    Sep. 2014, Biochimica et biophysica acta, 1837(9) (9), 1514 - 1521
    [Refereed]

  • Seiji Akimoto, Ayaka Teshigahara, Makio Yokono, Mamoru Mimuro, Ryo Nagao, Tatsuya Tomo
    Sep. 2014, BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS, 1837(9) (9), 1514 - 1521, English
    [Refereed]
    Scientific journal

  • Tatsuya Tomo, Toshiyuki Shinoda, Min Chen, Suleyman I. Allakhverdiev, Seiji Akimoto
    Sep. 2014, BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS, 1837(9) (9), 1484 - 1489, English
    [Refereed]
    Scientific journal

  • Ryo Nagao, Makio Yokono, Tatsuya Tomo, Seiji Akimoto
    Sep. 2014, JOURNAL OF PHYSICAL CHEMISTRY LETTERS, 5(17) (17), 2983 - 2987, English
    [Refereed]
    Scientific journal

  • Seiji Akimoto, Makio Yokono, Erina Yokono, Shimpei Aikawa, Akihiko Kondo
    Aug. 2014, PLANT PHYSIOLOGY AND BIOCHEMISTRY, 81, 149 - 154, English
    [Refereed]
    Scientific journal

  • Mie Araki, Seiji Akimoto, Mamoru Mimuro, Tohru Tsuchiya
    Aug. 2014, PLANT PHYSIOLOGY AND BIOCHEMISTRY, 81, 155 - 162, English
    [Refereed]
    Scientific journal

  • Ryo Nagao, Makio Yokono, Ayaka Teshigahara, Seiji Akimoto, Tatsuya Tomo
    May 2014, JOURNAL OF PHYSICAL CHEMISTRY B, 118(19) (19), 5093 - 5100, English
    [Refereed]
    Scientific journal

  • Yusuke Iima, Daiki Kuzuhara, Zhao-Li Xue, Seiji Akimoto, Hiroko Yamada, Keisuke Tominaga
    2014, PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 16(26) (26), 13129 - 13135, English
    [Refereed]
    Scientific journal

  • Ryosuke Hayashi, Ginga Shimakawa, Keiichiro Shaku, Satoko Shimizu, Seiji Akimoto, Hiroshi Yamamoto, Katsumi Amako, Toshio Sugimoto, Masahiro Tamoi, Amane Makino, Chikahiro Miyake
    2014, BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY, 78(3) (3), 384 - 393, English
    [Refereed]
    Scientific journal

  • Hiroaki Yamamoto, Kei Ohkubo, Seiji Akimoto, Shunichi Fukuzumi, Akihiko Tsuda
    2014, ORGANIC & BIOMOLECULAR CHEMISTRY, 12(36) (36), 7004 - 7017, English
    [Refereed]
    Scientific journal

  • 生命科学を理解するための蛍光の基礎Ⅱ（時間分解蛍光と異方性）
    秋本 誠志
    2014, 分光研究, 63(2) (2), 73–81, Japanese
    [Refereed]

  • Seiji Akimoto, Makio Yokono, Shimpei Aikawa, Akihiko Kondo
    Nov. 2013, PHOTOSYNTHESIS RESEARCH, 117(1-3) (1-3), 235 - 243, English
    [Refereed]
    Scientific journal

  • Muhammad Arba, Shimpei Aikawa, Kenta Niki, Makio Yokono, Akihiko Kondo, Seiji Akimoto
    Nov. 2013, CHEMICAL PHYSICS LETTERS, 588, 231 - 236, English
    [Refereed]
    Scientific journal

  • Ryo Nagao, Makio Yokono, Seiji Akimoto, Tatsuya Tomo
    American Chemical Society, Jun. 2013, Journal of Physical Chemistry B, 117(23) (23), 6888 - 6895, English
    [Refereed]
    Scientific journal

  • Koge Yuki, Murakami Akio, Akimoto Seiji
    The Biophysical Society of Japan General Incorporated Association, 2013, Seibutsu Butsuri, 53(1) (1), S201, English

  • Fumiya Hamada, Makio Yokono, Euichi Hirose, Akio Murakami, Seiji Akimoto
    Nov. 2012, BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS, 1817(11) (11), 1992 - 1997, English
    [Refereed]
    Scientific journal

  • Akimoto S, Yokono M, Hamada F, Teshigahara A, Aikawa S, Kondo A
    Aug. 2012, Biochimica et biophysica acta, 1817(8) (8), 1483 - 1489
    [Refereed]

  • Tatsuya Tomo, Hayato Kusakabe, Ryo Nagao, Hisashi Ito, Ayumi Tanaka, Seiji Akimoto, Mamoru Mimuro, Shigetoshi Okazaki
    Aug. 2012, BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS, 1817(8) (8), 1299 - 1305, English
    [Refereed]
    Scientific journal

  • Tohru Tsuchiya, Seiji Akimoto, Tadashi Mizoguchi, Kazuyuki Watabe, Hayato Kindo, Tatsuya Tomo, Hitoshi Tamiaki, Mamoru Mimuro
    Aug. 2012, BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS, 1817(8) (8), 1285 - 1291, English
    [Refereed]
    Scientific journal

  • Seiji Akimoto, Makio Yokono, Fumiya Hamada, Ayaka Teshigahara, Shimpei Aikawa, Akihiko Kondo
    Aug. 2012, BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS, 1817(8) (8), 1483 - 1489, English
    [Refereed]
    Scientific journal

  • Yokono M, Tomo T, Nagao R, Ito H, Tanaka A, Akimoto S
    May 2012, Biochimica et biophysica acta, 1817(5) (5), 754 - 759
    [Refereed]

  • Makio Yokono, Tatsuya Tomo, Ryo Nagao, Hisashi Ito, Ayumi Tanaka, Seiji Akimoto
    May 2012, BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS, 1817(5) (5), 754 - 759, English
    [Refereed]
    Scientific journal

  • Tohru Tsuchiya, Tadashi Mizoguchi, Seiji Akimoto, Tatsuya Tomo, Hitoshi Tamiaki, Mamoru Mimuro
    Mar. 2012, PLANT AND CELL PHYSIOLOGY, 53(3) (3), 518 - 527, English
    [Refereed]
    Scientific journal

  • Makio Yokono, Hiroko Uchida, Yuzuru Suzawa, Seiji Akimoto, Akio Murakami
    Feb. 2012, BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS, 1817(2) (2), 306 - 311, English
    [Refereed]
    Scientific journal

  • Yusuke Iima, Daiki Kuzuhara, Zhao-Li Xue, Hidemitsu Uno, Seiji Akimoto, Hiroko Yamada, Keisuke Tominaga
    Sep. 2011, CHEMICAL PHYSICS LETTERS, 513(1-3) (1-3), 67 - 71, English
    [Refereed]
    Scientific journal

  • Yasuo Yamauchi, Yukihiro Kimura, Seiji Akimoto, Yoko Marutani, Masaharu Mizutani, Yukihiro Sugimoto
    AbstractPlants are often exposed to temperatures of around 40^o^C. These temperatures can cause serious damage to photosystems, yet plants can survive with minimum damage. Here, we show that plants switch photosystem to protect photosystem II (PSII) at 40^o^C. Using wheat and Arabidopsis seedlings, we investigated the mechanisms of heat-derived damage in the dark and avoidance of damage in the light. Heat treatment at 40^o^C in the dark caused serious damage to PSII: the maximum quantum yield of PSII (Fv/Fm) and oxygen evolution rapidly decreased. The damage was due to the degradation of the D1 protein (shown by immuno-chemical analysis) and the disturbance of energy transfer in PSII core chlorophyll-binding proteins CP43 and CP47 (shown by time-resolved fluorescence measurement). The damage to PSII might be due to enhanced introduction of electrons from the reducing power of the stroma into thylakoid membranes, causing subsequent electron backflow to PSII. Plants treated at 40^o^C in the light avoided PSII damage and showed preferential excitation of photosystem I (PSI), phosphorylation and migration of light-harvesting complex II (LHCII), which indicate state transition of the photosystem to enhance thermal dispersion and light-driven cyclic electron flow around PSI. These results suggest that heat damage to PSII is probably due to a backflow of reducing power from the stroma to PSII, and that light causes a state transition of photosystem, driving cyclic electron flow and thus protecting PSII from damage.
    Springer Science and Business Media LLC, Aug. 2011, Nature Precedings
    Scientific journal

  • Makio Yokono, Akio Murakami, Seiji Akimoto
    Jul. 2011, BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS, 1807(7) (7), 847 - 853, English
    [Refereed]
    Scientific journal

  • Mamoru Mimuro, Akio Murakami, Tatsuya Tomo, Tohru Tsuchiya, Kazuyuki Watabe, Makio Yokono, Seiji Akimoto
    May 2011, BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS, 1807(5) (5), 471 - 481, English
    [Refereed]
    Scientific journal

  • Yasuhito Sakuraba, Makio Yokono, Seiji Akimoto, Ryouichi Tanaka, Ayumi Tanaka
    Jun. 2010, PLANT AND CELL PHYSIOLOGY, 51(6) (6), 1055 - 1065, English
    [Refereed]
    Scientific journal

  • Akimoto Seiji, Yokono Makio, Tada Megumi, Hamada Fumiya, Yamagishi Takahiro, Kawai Hiroshi
    The Biophysical Society of Japan General Incorporated Association, 2010, Seibutsu Butsuri, 50(2) (2), S195, English

  • Mamoru Mimuro, Makio Yokono, Seiji Akimoto
    Jan. 2010, PHOTOCHEMISTRY AND PHOTOBIOLOGY, 86(1) (1), 62 - 69, English
    [Refereed]
    Scientific journal

  • Tomo T, Akimoto S, Ito H, Tsuchiya T, Fukuya M, Tanaka A, Mimuro M
    Mar. 2009, Biochimica et biophysica acta, 1787(3) (3), 191 - 200
    [Refereed]

  • Tatsuya Tomo, Seiji Akimoto, Hisashi Ito, Tohru Tsuchiya, Michitaka Fukuya, Ayumi Tanaka, Mamoru Mimuro
    Mar. 2009, BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS, 1787(3) (3), 191 - 200, English
    [Refereed]
    Scientific journal

  • Yuichiro Shimada, Tohru Tsuchiya, Seiji Akimoto, Tatsuya Tomo, Michitaka Fukuya, Kazunori Tanaka, Mamoru Mimuro
    Oct. 2008, PHOTOSYNTHESIS RESEARCH, 98(1-3) (1-3), 303 - 314, English
    [Refereed]
    Scientific journal

  • Seiji Akimoto, Makio Yokono, Michiya Higuchi, Tatsuya Tomo, Shinichi Takaichi, Akio Murakami, Mamoru Mimuro
    Oct. 2008, PHOTOCHEMICAL & PHOTOBIOLOGICAL SCIENCES, 7(10) (10), 1206 - 1209, English
    [Refereed]
    Scientific journal

  • Tatsuya Tomo, Seiji Akimoto, Tohru Tsuchiya, Michitaka Fukuya, Kazunori Tanaka, Mamoru Mimuro
    Oct. 2008, PHOTOSYNTHESIS RESEARCH, 98(1-3) (1-3), 293 - 302, English
    [Refereed]
    Scientific journal

  • Tatsuya Tomo, Yuki Kato, Takehiro Suzuki, Seiji Akimoto, Tatsunori Okubo, Takumi Noguchi, Koji Hasegawa, Tohru Tsuchiya, Kazunori Tanaka, Michitaka Fukuya, Naoshi Dohmae, Tadashi Watanabe, Mamoru Mimuro
    Jun. 2008, JOURNAL OF BIOLOGICAL CHEMISTRY, 283(26) (26), 18198 - 18209, English
    [Refereed]
    Scientific journal

  • Yokono M, Akimoto S, Tanaka A
    Apr. 2008, Biochimica et biophysica acta, 1777(4) (4), 379 - 387
    [Refereed]

  • Makio Yokono, Seiji Akimoto, Ayumi Tanaka
    Apr. 2008, BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS, 1777(4) (4), 379 - 387, English
    [Refereed]
    Scientific journal

  • Kohel Koyama, Hiroyuki Suzuki, Takumi Noguchi, Seiji Akimoto, Tohru Tsuchiya, Mamoru Mimuro
    Apr. 2008, BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS, 1777(4) (4), 369 - 378, English
    [Refereed]
    Scientific journal

  • Yokono M, Akimoto S, Koyama K, Tsuchiya T, Mimuro M
    Jan. 2008, Biochimica et biophysica acta, 1777(1) (1), 55 - 65
    [Refereed]

  • Ultrafast relaxation dynamics of a keto-carotenoid, siphonaxanthin, probed by time-resolved fluorescence
    Akimoto S, Yokono M, Higuchi M, MURAKAMI Akio, Takaichi S, Mimuro M
    2008, Photosynthesis. Energy of Sun (Springer, Dordrecht), pp.319-322, English
    [Refereed]
    Scientific journal

  • Unique optical properties of LHC II isolated from Codium fragile - its correlation to protein environment
    Tohru Tsuchiya, Tatsuya Tomo, Seiji Akimoto, Akio Murakami, Mamoru Mimuro
    2008, Photosynthesis Energy from the Sun, 1, 343 - 346, English
    [Refereed]

  • クロロフィル分子の多様性に基づく光合成の光エネルギー変換系の基本原理の解明化
    三室 守, 鞆 達也, 土屋 徹, 野口 巧, 大久保 辰則, AKIMOTO SEIJI, 横野 牧生, 井上 和仁
    The composition of photosystem II (PSII) in the chlorophyll (Chl) d-dominated cyanobacterium Acaryochloris marina MBIC 11017 was investigated to enhance the general understanding of the energetics of the PSII reaction center. We first purified photochemically active complexes consisting of a 47 kDa chlorophyll protein (CP47), CP43' (PcbC), D1, D2, cytochrome b_<559>, PsbI, and an unknown small polypeptide. The pigment composition per two pheophytin (Phe) a molecules was 55±7 Chl d, 3.0±0.4 Chl a, 17±3 α-carotene, and 1.4±0.2 plastoquinone-9. A special pair was detected by a reversible absorption change at 713 nm (P713) together with a cation radical band at 842 nm. FTIR difference spectra of the specific bands of a 3-formyl group allowed assignment of the special pair. The combined results indicate that the special pair includes a Chl d homodimer. The primary electron acceptor was shown by photoaccumulation to be Phe a, and its potential was shifted to a higher value than that in the Chl a/Phe a system. The overall energetics of PSII in the Chl d system adapt to changes in the redox potentials, with P713 as the special pair utilizing lower light energy at 713 nm. Our findings support the idea that changes in photosynthetic pigments combine with modification of the redox potentials of electron transfer components to give rise to energy changes in the total reaction system.
    Kanagawa University, 2008, Science Journal of Kanagawa University, 19, 39 - 44, Japanese
    [Refereed]
    Scientific journal

  • Makio Yokono, Seiji Akimoto, Kohei Koyama, Tohru Tsuchiya, Mamoru Mimuro
    Jan. 2008, BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS, 1777(1) (1), 55 - 65, English
    [Refereed]
    Scientific journal

  • Seiji Akimoto, Tatsuya Tomo, Yukito Naitoh, Akira Otomo, Akio Murakami, Mamoru Mimuro
    Aug. 2007, JOURNAL OF PHYSICAL CHEMISTRY B, 111(31) (31), 9179 - 9181, English
    [Refereed]
    Scientific journal

  • Tatsuya Tomo, Tatsunori Okubo, Seiji Akimoto, Makio Yokono, Hideaki Miyashita, Tohru Tsuchiya, Takumi Noguchi, Mamoru Mimuro
    Apr. 2007, PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 104(17) (17), 7283 - 7288, English
    [Refereed]
    Scientific journal

  • Identification of the special pair of photosystem II in a chlorophyll d-dominated cyanobacterium
    Tatsuya Tomo, Tatsunori Okubo, Seiji Akimoto, Makio Yokono, Hideaki Miyashita, Tohru Tsuchiya, Takumi Noguchi, Mamoru Mimuro
    Apr. 2007, Proceedings of the National Academy of Sciences of the United States of America, 104・17・7283–7288, English
    [Refereed]
    Scientific journal

  • Mamoru Mimuro, Seiji Akimoto, Tatsuya Tomo, Makio Yokono, Hideaki Miyashita, Tohru Tsuchiya
    Apr. 2007, BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS, 1767(4) (4), 327 - 334, English
    [Refereed]
    Scientific journal

  • Application of time-resolved polarization fluorescence spectroscopy in the femtosecond range to photosynthetic systems.
    Akimoto Seiji, M. Mimuro
    Jan. 2007, Photochem. Photobiol., 83・1・163-170, English
    [Refereed]
    Scientific journal

  • Seiji Akimoto, Mamoru Mimuro
    Jan. 2007, PHOTOCHEMISTRY AND PHOTOBIOLOGY, 83(1) (1), 163 - 170, English
    [Refereed]
    Scientific journal

  • Shin-Ichiro Sato, Takashi Nakamura, Satoru Nitobe, Takayuki Kiba, Kiyotada Hosokawa, Tatsuya Kasajima, Issei Otsuka, Seiji Akimoto, Toyoji Kakuchi
    American Chemical Society, Nov. 2006, Journal of Physical Chemistry B, 110(43) (43), 21444 - 21449, English
    [Refereed]
    Scientific journal

  • K Koyama, T Tsuchiya, S Akimoto, M Yokono, H Miyashita, M Mimuro
    Jun. 2006, FEBS LETTERS, 580(14) (14), 3457 - 3461, English
    [Refereed]
    Scientific journal

  • Masayuki Okamura, Kojiro Ebina, Seiji Akimoto, Iwao Yamazaki, Kohei Uosaki
    Mar. 2006, Journal of Photochemistry and Photobiology A: Chemistry, 178(2-3) (2-3), 156 - 161, English
    [Refereed]
    Scientific journal

  • Takayuki Kiba, Shin-Ichiro Sato, Seiji Akimoto, Tatsuya Kasajima, Iwao Yamazaki
    Mar. 2006, Journal of Photochemistry and Photobiology A: Chemistry, 178(2-3) (2-3), 201 - 207, English
    [Refereed]
    Scientific journal

  • S Akimoto, A Murakami, M Yokono, K Koyama, T Tsuchiya, H Miyashita, Yamazaki, I, M Mimuro
    Mar. 2006, JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY, 178(2-3) (2-3), 122 - 129, English
    [Refereed]
    Scientific journal

  • S Akimoto, M Yokono, M Ohmae, Yamazaki, I, N Nagata, R Tanaka, A Tanaka, M Mimuro
    Jun. 2005, CHEMICAL PHYSICS LETTERS, 409(4-6) (4-6), 167 - 171, English
    [Refereed]
    Scientific journal

  • S Akimoto, M Yokono, M Ohmae, Yamazaki, I, A Tanaka, M Higuchi, T Tsuchiya, H Miyashita, M Mimuro
    Jun. 2005, JOURNAL OF PHYSICAL CHEMISTRY B, 109(25) (25), 12612 - 12619, English
    [Refereed]
    Scientific journal

  • 秋本誠志, 木場隆之, 横野牧生, 三室守, 山崎巌
    A femtosecond time-resolved fluorescence spectrometer has been constructed using the up-conversion system performed with a Ti: Sapphire laser. The angle of a BBO crystal, the compensation for time-zero dispersion, and the direction of laser polarization were automatically controlled by a computer. Representative data were obtained on coumarin 153 in acetone. This system will be applied to measurements of ultrafast relaxation processes in the time region from several tens of femtoseconds to several tens of picoseconds.
    The Spectroscopical Society of Japan, Feb. 2005, 分光研究, 54(1) (1), 18 - 22, Japanese

  • Yokono M., Ohamae M., Akimoto S., Yamazaki I., Nagata N., Tanaka A., Mimuro M.
    The Biophysical Society of Japan General Incorporated Association, 2005, Seibutsu Butsuri, 45, S275, Japanese

  • Murai Y., Yokono M., Akimoto S., Yamazaki I., Murakami A., Higuchi M., Mimuro M.
    The Biophysical Society of Japan General Incorporated Association, 2005, Seibutsu Butsuri, 45, S275, Japanese

  • Yamazaki, I, S Akimoto, N Aratani, A Osuka
    Nov. 2004, BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 77(11) (11), 1959 - 1971, English
    [Refereed]
    Scientific journal

  • Makoto Obata, Norie Tanihara, Misaki Nakai, Masafumi Harada, Seiji Akimoto, Iwao Yamazaki, Akio Ichimura, Isamu Kinoshita, Masahiro Mikuriya, Mikio Hoshino, Shigenobu Yano
    Oct. 2004, Dalton Transactions, (20) (20), 3283 - 3287, English
    [Refereed]
    Scientific journal

  • S Akimoto, Yamazaki, I, A Murakami, S Takaichi, M Mimuro
    May 2004, CHEMICAL PHYSICS LETTERS, 390(1-3) (1-3), 45 - 49, English
    [Refereed]
    Scientific journal

  • Tatsuya Kasajima, Seiji Akimoto, Shin-Ichiro Sato, Iwao Yamazaki
    Apr. 2004, Journal of Physical Chemistry A, 108(16) (16), 3268 - 3275, English
    [Refereed]
    Scientific journal

  • Mamoru Mimuro, Seiji Akimoto, Takanori Gotoh, Makio Yokono, Machiko Akiyama, Tohru Tsuchiya, Hideaki Miyashita, Masami Kobayashi, Iwao Yamazaki
    Elsevier, Jan. 2004, FEBS Letters, 556(1-3) (1-3), 95 - 98, English
    [Refereed]
    Scientific journal

  • Higuchi M., Mimuro M., Yokono M., Murai Y., Oomae A., Akimoto S., Yamazaki I.
    The Biophysical Society of Japan General Incorporated Association, 2004, Seibutsu Butsuri, 44, S174, Japanese

  • Tatsuya Kasajima, Seiji Akimoto, Shin-Ichiro Sato, Iwao Yamazaki
    Jun. 2003, Chemical Physics Letters, 375(1-2) (1-2), 227 - 232, English
    [Refereed]
    Scientific journal

  • Yamazaki, I, N Aratani, S Akimoto, T Yamazaki, A Osuka
    Jun. 2003, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 125(24) (24), 7192 - 7193, English
    [Refereed]
    Scientific journal

  • Yasuhiro Arima, Seiji Akimoto, Tomoko Yamazaki, Minako Shibata, Shiho Hirohara, Shigenobu Yano, Toyoji Kakuchi, Iwao Yamazaki
    Jul. 2002, Chemical Physics Letters, 361(1-2) (1-2), 152 - 158, English
    [Refereed]
    Scientific journal

  • M Mimuro, T Ookubo, D Takahashi, T Sakawa, S Akimoto, Yamazaki, I, H Miyashita
    Jun. 2002, PLANT AND CELL PHYSIOLOGY, 43(6) (6), 587 - 594, English
    [Refereed]
    Scientific journal

  • Iwao Yamazaki, Seiji Akimoto, Tomoko Yamazaki, Shin-Ichiro Sato, Yoshiteru Sakata
    Mar. 2002, Journal of Physical Chemistry A, 106(10) (10), 2122 - 2128, English
    [Refereed]
    Scientific journal

  • S Akimoto, Yamazaki, I, T Sakawa, M Mimuro
    Mar. 2002, JOURNAL OF PHYSICAL CHEMISTRY A, 106(10) (10), 2237 - 2243, English
    [Refereed]
    Scientific journal

  • Aiko Nakano, Atsuhiro Osuka, Tomoko Yamazaki, Yoshinobu Nishimura, Seiji Akimoto, Iwao Yamazaki, Akira Itaya, Masataka Murakami, Hiroshi Miyasaka
    Jul. 2001, Chemistry - A European Journal, 7(14) (14), 3134 - 3151, English
    [Refereed]
    Scientific journal

  • 秋本 誠志, 山崎 巌, 安藤 正典
    The Spectroscopical Society of Japan, Jun. 2001, 分光研究 = Journal of the spectroscopical research of Japan, 50(3) (3), 116 - 117, Japanese

  • Excitation relaxation dynamics of linear carotenoids
    S Akimoto, Yamazaki, I, S Takaichi, M Mimuro
    May 2000, JOURNAL OF LUMINESCENCE, 87-9, 797 - 799, English
    [Refereed]
    Scientific journal

  • Excitation relaxation of carotenoids within the S-2 state probed by the femtosecond fluorescence up-conversion method
    S Akimoto, Yamazaki, I, S Takaichi, M Mimuro
    Nov. 1999, CHEMICAL PHYSICS LETTERS, 313(1-2) (1-2), 63 - 68, English
    [Refereed]
    Scientific journal

  • Ultrafast excitation transfer and relaxation in linear and crossed-linear arrays of porphyrins
    S Akimoto, T Yamazaki, Yamazaki, I, A Nakano, A Osuka
    Nov. 1999, PURE AND APPLIED CHEMISTRY, 71(11) (11), 2107 - 2115, English
    [Refereed]
    Scientific journal

  • S Akimoto, T Yamazaki, Yamazaki, I, A Osuka
    Aug. 1999, CHEMICAL PHYSICS LETTERS, 309(3-4) (3-4), 177 - 182, English
    [Refereed]
    Scientific journal

  • Mark H. Wall Jr., Seiji Akimoto, Tomoko Yamazaki, Nobuhiro Ohta, Iwao Yamazaki, Takuya Sakuma, Hiroaki Kido
    Jul. 1999, Bulletin of the Chemical Society of Japan, 72(7) (7), 1475 - 1481, English
    [Refereed]
    Scientific journal

  • M Mimuro, S Akimoto, Yamazaki, I, H Miyashita, S Miyachi
    May 1999, BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS, 1412(1) (1), 37 - 46, English
    [Refereed]
    Scientific journal

  • A. Osuka, A. Nakano, H. Shiratori, S. Akimoto, Y. Nishimura, T. Yamazaki, I. Yamazaki
    Institute of Electrical and Electronics Engineers Inc., 1999, CLEO/Pacific Rim 1999 - Pacific Rim Conference on Lasers and Electro-Optics, 1, 108 - 109, English
    [Refereed]
    International conference proceedings

  • Ultrafast energy relaxation and excitation delocalization in excited states of zinc porphyrin dimers and trimer
    Yamazaki, I, S Akimoto, T Yamazaki
    Jan. 1999, ACTA PHYSICA POLONICA A, 95(1) (1), 105 - 120, English
    [Refereed]
    Scientific journal

  • Fluorescence properties of chlorophyll d-dominating prokaryotic alga, Acaryochloris marina.
    M Mimuro, S Akimoto, Yamazaki, I, H Miyashita, S Miyachi
    1998, PHOTOSYNTHESIS: MECHANISMS AND EFFECTS, VOLS I-V, 1025 - 1028, English
    [Refereed]
    International conference proceedings

  • Excimer formation of cyanobiphenyls in calix[4]resorecinarene derivative probed by picosecond time-resolved fluorescence spectroscopy
    S Akimoto, H Nishizawa, T Yamazaki, Yamazaki, I, Y Hayashi, M Fujimaki, K Ichimura
    Sep. 1997, CHEMICAL PHYSICS LETTERS, 276(5-6) (5-6), 405 - 410, English
    [Refereed]
    Scientific journal

  • Effect of molecular structures and solvents on the excited state dynamics of the S-2 state of carotenoids analyzed by the femtosecond up-conversion method
    M Mimuro, S Akimoto, S Takaichi, Yamazaki, I
    Feb. 1997, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 119(6) (6), 1452 - 1453, English
    [Refereed]
    Scientific journal

  • I. Yamazaki, M. Yamaguchi, N. Okada, S. Akimoto, T. Yamazaki, N. Ohta
    Elsevier, 1997, Journal of Luminescence, 72-74, 71 - 74, English
    [Refereed]
    Scientific journal

  • Ikuo Mukai, Kei Abe, Seiji Akimoto, Takashi Ito, Nobuhiro Ohta, Iwao Yamazaki
    Chemical Society of Japan, 1997, Chemistry Letters, (3) (3), 263 - 264, English
    [Refereed]
    Scientific journal

  • Toshihiro Nakayama, Seiji Akimoto, Iwao Yamazaki, Kumao Hamanoue
    Elsevier, 1997, Journal of Photochemistry and Photobiology A: Chemistry, 104(1-3) (1-3), 77 - 81, English
    [Refereed]
    Scientific journal

  • Excitation energy transfer in carotenoid-chlorophyll protein complexes probed by femtosecond fluorescence decays
    S Akimoto, S Takaichi, T Ogata, Y Nishimura, Yamazaki, I, M Mimuro
    Sep. 1996, CHEMICAL PHYSICS LETTERS, 260(1-2) (1-2), 147 - 152, English
    [Refereed]
    Scientific journal

  • Kei Abe, Sachiko Suzuki, Ikuo Mukai, Seiji Akimoto, Nobuhiro Ohta, Iwao Yamazaki
    Chemical Society of Japan, 1996, Chemistry Letters, (6) (6), 479 - 480, English
    [Refereed]
    Scientific journal

  • AKIMOTO Seiji, NISHIMURA Yoshinobu, YAMAZAKI Iwao, WATANABE Motoyuki, KOISHI Musubu
    The Spectroscopical Society of Japan, 1994, Bunko Kenkyu, 43(3) (3), 164 - 170, Japanese

■ MISC
  • Mana Nakayasu, Seiji Akimoto, Kohei Yoneda, Soichiro Ikuta, Ginga Shimakawa, Yusuke Matsuda
    Abstract Photosynthesis needs light energy, but that exceeding the maximal capacity of photosynthesis enhances formation of reactive oxygen species, which potentially causes photodamages. Therefore, light-harvesting complexes (Lhc) in phototrophs harbor various proteins and pigments to function in both light capture and energy dissipation. Diatom Lhcx proteins are reported to be a critical component for thermal dissipation of excess light energy, but the molecular mechanism of photoprotection is still not fully understood and the functions of each Lhcx isoform are not yet differentiated. Here, we focused on two types of Lhcx isoforms inThalassiosira pseudonana: TpLhcx1/2, putative major components for energy-dependent fluorescence quenching (qE); and TpLhcx6_1, functionally unknown isoform uniquely conserved in Thalassiosirales. TpLhcx1/2 proteins accumulated more under high light than under low light, while the TpLhcx6_1 protein level was constitutive irrespective of light intensities and CO2 concentrations. High-light induced photodamage of photosystem II was increased in the genome-editing transformants of these Lhcx isoforms relative to the wild-type. Transformants lacking TpLhcx1/2 showed significantly lowered qE capacities, strongly suggesting that these proteins are important for the fast thermal energy dissipation. While in contrast, genome-editing transformants lacking the TpLhcx6_1 protein rather increased the qE capacity. TpLhcx6_1 transformants were further evaluated by the low-temperature time-resolved chlorophyll fluorescence measurement, showing the longer fluorescence lifetime in transformants than that in the wild type cells even at the dark-acclimated state of these cells. These results suggest that TpLhcx6_1 functions in photoprotection through non-photochemical energy dissipation in the different way from qE. One sentence summary The marine diatomThalassiosira pseudonanadissipates excess light energy for photoprotectionviatwo types of mechanisms supported by different Lhc isofoms.
    Cold Spring Harbor Laboratory, 19 Apr. 2024

  • Unique adaptation for oxygenic photosynthesis under far-red light in a freshwater eukaryotic alga Neochloris sp. Biwa 5-2 (Sphaeropleales, Chlorophyceae)
    WANG Fei, AKIMOTO Seiji, MIYASHITA Hideaki
    2024, 藻類, 72(1) (1)

  • Diversity of responses to different light conditions in excitation energy transfer of cyanobacteria
    Seiji Akimoto
    Lead, Jan. 2024, Proceedings of the17th DAE-BRANS Biennial Trombay Symposium on Radiation & Photochemistry (ISBN 978-81-957780-9-6)
    [Invited]

  • Analysis of photosynthetic electron flow in cyanobacteria by FBA simulation
    豊島正和, 豊島正和, 山本千晶, 植野嘉文, 戸谷吉博, 秋本誠志, 清水浩
    2021, 日本生物工学会大会講演要旨集, 73rd

  • ハマサンゴの骨格から分離した糸状緑藻Phaeophila dendroidesによる遠赤色光の利用
    大波千恵子, 西堀洋平, 植野嘉文, 須田彰一郎, 神川龍馬, 秋本誠志, 宮下英明
    2021, 藻類, 69(1) (1)

  • Analysis of regulatory signals for redox balance-sensing phycobilisome degradation using ΔndhD1/D2 strain of Synechocystis sp. PCC 6803
    豊島正和, 阪田真澄, 山本千晶, 植野嘉文, 戸谷吉博, 秋本誠志, 清水浩
    2021, 日本植物生理学会年会(Web), 62nd

  • 異なる波長の光照射下におけるシアノバクテリアの光合成と代謝のシミュレーション予測による適応機構の解析
    豊島正和, 山本千晶, 植野嘉文, 戸谷吉博, 秋本誠志, 清水浩
    2020, 日本植物学会大会研究発表記録(CD-ROM), 84th

  • Light-harvesting and energy transfer processes by low-energy chlorophylls in photosynthesis
    S. Akimoto, Y. Ueno, M. Yokono, S.I. Allakhverdiev, T. Tomo, J.R. Shen, R. Nagao
    Lead, Dec. 2019, Proceedings of the15th DAE-BRANS Biennial Trombay Symposium on Radiation & Photochemistry (ISBN 978-81-940321-5-1), English
    [Invited]
    Introduction international proceedings

  • 光化学系超複合体の機能解明
    AKIMOTO SEIJI
    カーボン・エネルギーコントロール社会協議会 (CanApple), Sep. 2018, CanAppleニュース, 45, Japanese
    [Invited]
    Introduction other

  • 明所高温条件で誘導されるステート2によるPSII障害回避機構の解析
    丸谷曜子, 山内靖雄, 東山真理, 秋本誠志, 井上加奈子, 池田健一, 水谷正治, 杉本幸裕
    2015, 日本植物生理学会年会要旨集, 56th

  • 1P-191 The effect of sea-salts on the cell-growth and photosynthesis in a remarkable carbon feedstock Spirulina
    Aikawa Shimpei, Akimoto Seiji, Hasunuma Tomohisa, Kondo Akihiko
    日本生物工学会, 2013, 日本生物工学会大会講演要旨集, 65, 65 - 65, Japanese

  • Cyanobacterium Synechocystis sp. PCC6803 におけるO2存性オルタナティブ・エレクトロン・フロー (AEF)の生理的役割
    林 良祐, 清水 聡子, 山本 宏, 藍川 晋平, 蓮沼 誠久, 秋本 誠志, 近藤 昭彦, 三宅 親弘
    Mar. 2012, 第53回日本植物生理学会, Japanese

  • 11 シアノバクテリアでのオルタナティブ・エレクトロン・フロー(AEF)評価系の確立(関西支部講演会,2010年度各支部会講演要旨)
    進藤 沙織, 林 吉祐, 真野 陽人, 杉本 敏男, 近藤 昭彦, 藍川 晋平, 蓮沼 誠久, 秋本 誠志, 三宅 親弘
    一般社団法人日本土壌肥料学会, 08 Aug. 2011, 日本土壌肥料学会講演要旨集, (57) (57), 329 - 329, Japanese

  • Solvation dynamics in aqueous solutions: Relation to terahertz time-domain spectroscopy and infrared nonlinear spectroscopy
    Keisuke Tominaga, Mami Takatsuka, Akina Kariya, Akane Ishihara, Junpei Tayama, Motohiro Banno, Kaoru Ohta, Shinji Saito, Seiji Akimoto
    Aug. 2011, ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, 242, English
    Summary international conference

  • 高温ストレスを受けたコムギにおいてステート遷移により移動するLHCIIタンパク質の解析
    丸谷曜子, 山内靖雄, 秋本誠志, 水谷正治, 杉本幸裕
    2011, 日本農芸化学会関西支部講演会講演要旨集, 472nd

  • シクロデキストリン連結亜鉛ポルフィリンのJ会合体形成および励起緩和ダイナミクス
    木場隆之, 鈴木広樹, 細川清正, 秋本誠志, 覚知豊次, 佐藤信一郎
    2008, 化学反応討論会講演要旨集, 24th

  • シクロデキストリン包接現象を利用した亜鉛ポルフィリンJ会合体形成
    木場隆之, 細川清正, 鈴木広樹, 馬場真吾, 秋本誠志, 覚知豊次, 佐藤信一郎
    2008, 分子科学討論会講演プログラム&要旨(Web), 2nd

  • Identification of special pair and ChlZ of Photosystem II in Acaryochloris marina
    T Tomo, T Okubo, S Akimoto, H Miyashita, T Tsuchiya, T Noguchi, M Mimuro
    Jul. 2007, 14th International Congress of Photosynthesis, Jul. 22-27, 2007, Glasgow (UK), English

  • Excitation energy transfer in PS I of the cyanobacterium Gloeobacter violaceus PCC 7421 that lacks the long-wavelength form of chlorophyll a
    M Mimuro, M Higuchi, H Inoue, M Yokono, T Tsuchiya, H Miyashita, S Akimoto
    Jul. 2007, 14th International Congress of Photosynthesis, Jul. 22-27, 2007, Glasgow (UK), English

  • 溶液中におけるケトカロテノイドの超高速励起緩和
    秋本誠志, 村井陽介, 横野牧生, 村上明男, 高市真一, 樋口倫也, 鞆達也, 三室守
    12 Jun. 2007, 化学反応討論会講演要旨集, 23rd, 90, Japanese

  • 横野牧生, 秋本誠志, 岸本純子, 田中歩
    15 Mar. 2007, 日本植物生理学会年会要旨集, 48th, 256, Japanese

  • Excitation energy transfer within the PSI-LHCI/II supercomplex from Chlamydomonas reinhardtii cells in state 2
    J. Minagawa, M. Yokono, M. Iwai, S. Akimoto
    Feb. 2007, PHOTOSYNTHESIS RESEARCH, 91(2-3) (2-3), 251 - 251, English
    Summary international conference

  • Unique optical properties of LHC II isolated from Codium fragile - its correlation to protein environment
    T. Tsuchiya, T. Tomo, S. Akimoto, A. Murakami, M. Mimuro
    Feb. 2007, PHOTOSYNTHESIS RESEARCH, 91(2-3) (2-3), 164 - 164, English
    Summary international conference

  • 溶液中におけるシフォナキサンチンの励起緩和過程
    村井陽介, 横野牧生, 秋本誠志, 村上明男, 高市真一, 樋口倫也, 三室守
    20 Jan. 2007, 日本化学会北海道支部研究発表会講演要旨集, 2007, 85, Japanese

  • 溶液中S1ペリレンにおける振動緩和速度の溶媒依存性
    木場隆之, 秋本誠志, 笠嶋辰也, 佐藤信一郎
    2007, 分子科学討論会講演要旨集(CD-ROM), 1st

  • Seasonal changes of excitation energy transfer in evergreen tree Taxus cuspidate
    Makio Yokono, Seiji Akimoto, Junko Kishimoto, Ayumi Tanaka
    2007, PLANT AND CELL PHYSIOLOGY, 48, S178 - S178, English
    Summary international conference

  • Tomo Tatsuya, Okubo Tatsunori, Akimoto Seiji, Yokono Makio, Miyashita Hideaki, Tsuchiya Tohru, Noguchi Takumi, Mimuro Mamoru
    <I>Acaryochloris marina</I> is a unique prokaryote in which Chl <I>d</I> is a major pigment. The Chl <I>a</I> content of <I>A. marina</I> is variable, but it is always present. The primary electron donor of <I>A. marina</I> PS I was assigned to Chl <I>d</I> by Hu et al. In contrast, the primary electron donor of PS II is still under debate. Delayed fluorescence of PS II in the ns range was found only in Chl <I>a</I> region in intact cells. To identify the primary electron donor, we isolated the PS II particle from <I>A. marina</I> by a combination of two kinds of chromatography and sucrose density gradient centrifugation. The purified PS II preparation contained Chl <I>d</I>, Chl <I>a</I>, Pheo <I>a</I>, and &alpha;-carotene. Furthermore, PS II complexes retained electron transfer activity. Based on these observations, the assignment of the pigment and its role of PS II RC will be discussed.
    The Japanese Society of Plant Physiologists, 2007, Plant and Cell Physiology Supplement, 2007(0) (0), 332 - 332

  • Energy transfer dynamics in phycobilisomes of Gloeobactei・violaceus PCC 7421
    M. Yokono, S. Akimoto, K. Koyama, T. Tsuchiya, H. Miyashita, M. Mimuro
    Nov. 2006, 3rd Asia and Oceania Conference on Photobiology, Nov. 2006, Beijing (China), English

  • Characterization of photosystem II in the chlorophyll d-dominated cyanobacteriaum Acaryochloris marina 11017
    T. Tomo, S. Akimoto, M. Yolcono, T. Tsuchiya, H. Miyashita, M. Mimuro
    Nov. 2006, 3rd Asia and Oceania Conference on Photobiology, Nov .2006, Beijing (China), English

  • シ アノバクテリア，Gloeobacter violaceus PCC 7421 から分離した光化学系Ⅰ粒子の分光学的特性
    三室 守, 井上英俊, 樋口倫也, 秋本誠志, 横野牧生, 土屋 徹, 宮下英明
    Jun. 2006, 第14 回 光合成の色素系と反応中心に関するセミナー, 2006 年6 月， 京都大学, Japanese

  • Gloeobacter violaceus PCC 7421 におけるエネルギー移動過程の解析
    横野牧生, 秋本誠志, 小山公平, 土屋 徹, 宮下英明, 三室 守
    Jun. 2006, 第14 回 光合成の色素 系と反応中心に関するセミナー, 2006 年6 月， 京都大学, Japanese

  • アントラセン誘導体とシクロデキストリン包接錯体の構造とダイナミクス
    仁戸部覚, 木場隆之, 秋本誠志, 中野環, 覚知豊次, 佐藤信一郎
    2006, 分子構造総合討論会講演要旨集(CD-ROM), 2006

  • シクロデキストリン・ナノキャビティー中におけるアントラセン誘導体の分子二量体形成
    仁戸部覚, 木場隆之, 佐藤信一郎, 秋本誠志
    2006, 日本化学会北海道支部研究発表会講演要旨集, 2006

  • Akiomto S., Murakami A., Yokono M., Koyama K., Tsuchiya T., Miyashita H., Yamazaki I., Mimuro M.
    The Biophysical Society of Japan General Incorporated Association, Nov. 2005, Seibutsu Butsuri, 45, S274, Japanese

  • 光捕集機能をもつカロテノイドの溶液中における励起緩和ダイナミクス
    村井陽介, 横野牧生, 秋本誠志, 山崎巌, 村上明男, 樋口倫也, 三室守
    15 Jul. 2005, 日本化学会北海道支部研究発表会講演要旨集, 2005, 145, Japanese

  • ペリレン濃厚溶液における蛍光量子ビート
    木場隆之, 佐藤信一郎, 秋本誠志, 笠嶋辰也, 山崎巌
    2005, 分子構造総合討論会講演要旨集(CD-ROM), 2005

  • シクロデキストリン・ナノキャビティ中における芳香族分子の電子位相緩和過程
    木場隆之, 佐藤信一郎, 秋本誠志, 笠嶋辰也, 山崎巌
    2005, 日本化学会北海道支部研究発表会講演要旨集, 2005

  • 光合成細菌における酸素の存在に応答したカロテノイドの分子種と機能の変換
    樋口倫也, 秋本誠志, 横野牧生, 宮下英明, 土屋徹, 山崎巌, 三室守
    2005, 日本光医学・光生物学会, 27th, 50, Japanese

  • Acaryochloris marinaのP740はChl d/d′ヘテロダイマーである
    後藤高紀, 宮下英明, 秋山満知子, 伊藤由加, 土屋徹, 秋本誠志, 山崎巌, 住斉, 三室守
    20 Mar. 2004, 日本植物生理学会年会要旨集, 45th, 115, Japanese

  • Excitation energy transfer in a primitive cyanobacteria Gloeobacter violaceus PCC 7421
    横野牧生, 秋本誠志, 山崎巌, 土屋徹, 宮下英明, 三室守
    11 Mar. 2004, 日本化学会講演予稿集, 84th(1) (1), 73, Japanese

  • クロロフィルa は光合成酸素発生に必須の成分である
    三室 守, 秋本誠志, 後藤高紀, 横野牧生, 秋山満知子, 土屋 徹, 宮下英明, 小林正美, 山崎 巌
    Mar. 2004, 第45 回日本植物生理学会, 2004 年3 月27-29 日, 八王子, Japanese

  • S1ペリレンのSolvent-assisted IVR
    木場隆之, 秋本誠志, 笠嶋辰也, 佐藤信一郎, 山崎巌
    2004, 化学反応討論会講演要旨集, 20th

  • ケトン系溶媒中S1ペリレンの振動緩和:solvent-assisted IVR
    木場隆之, 秋本誠志, 笠嶋辰也, 佐藤信一郎, 山崎巌
    2004, 日本化学会北海道支部研究発表会講演要旨集, 2004

  • シクロデキストリン・ナノキャビティ中におけるペリレンの励起緩和ダイナミクス
    木場隆之, 佐藤信一郎, 秋本誠志, 笠嶋辰也, 山崎巌
    2004, 光化学討論会講演要旨集, 2004

  • Chlorophyll a is necessary for oxygen evolution in oxygenic photosynthesis.
    M Mimuro, S Akimoto, T Goto, M Yokono, M Akiyama, T Tuchiya, H Miyashita, M Kobayashi, Yamazaki, I
    2004, PLANT AND CELL PHYSIOLOGY, 45, S79 - S79, English
    Summary international conference

  • Chlorophyll d '/PS1 stoichiometry in a chlorophyll d-dominated cyanobacterium Acaryochloris marina
    T Gotoh, H Miyashita, M Akiyama, Y Itoh, T Tsuchiya, S Akimoto, Yamazaki, I, H Sumi, M Mimuro, M Kobayashi
    2004, PLANT AND CELL PHYSIOLOGY, 45(0) (0), S42 - S42, English
    Summary international conference

  • 始原的シアノバクテリアGloeobacter violaceus PCC 7421におけるエネルギー移動過程の解析
    横野牧生, 秋本誠志, 山崎巌, 土屋徹, 宮下英明, 三室守
    15 Nov. 2003, 光化学討論会講演要旨集, 2003, 293, Japanese

  • Chl dを主要な光合成色素とするシアノバクテリアAcaryochloris marinaにおける光化学系II初発電子供与体の同定
    秋本誠志, 横野牧生, 山崎巌, 小林正美, 秋山満知子, 後藤高紀, 土屋徹, 宮下英明, 三室守
    15 Nov. 2003, 光化学討論会講演要旨集, 2003, 228, Japanese

  • Molecular architecture of photosynthetic systems of a primitive cyanobacterium Gloeobacter violaceus
    Mimuro, M, Miyashita,H, Tsuchiya,T, Satoh,S, Tanaka,A, Kaneko, T, Tabata,S, Akimoto,S, Yamazaki,I
    Oct. 2003, International symposium on Tetrapyrrole photoreceptors in photosynthetic organisms.PCC 7421. Oct. 2003, Passau (Germany), English

  • Excitataion Energy Transfer Processes and Mechanisms in Photosynthetic Antenna System : Analyses by Femtosecond and Picosecond Time-Resolved Fluorescence Spectroscopy
    MIMURO Mamoru, AKIMOTO Seiji, YAMAZAKI Iwao
    レ-ザ-学会, 15 Mar. 2003, The Review of laser engineering, 31(3) (3), 212 - 218, Japanese

  • Excitation Relaxation Dynamics of Carotenoids in Solutions and in photosynthetic Pigment Protein Complexes
    AKIMOTO Seiji, YAMAZAKI Iwao, MIMURO Mamoru
    レ-ザ-学会, 15 Mar. 2003, The Review of laser engineering, 31(3) (3), 207 - 211, Japanese

  • S1ペリレンの振動緩和-遅いIVR領域における溶質-溶媒弾性衝突効果-
    木場隆之, 秋本誠志, 笠嶋辰也, 佐藤信一郎, 山崎巌
    2003, 光化学討論会講演要旨集, 2003

  • Analyses of excitation energy transfer processes from siphonaxanthin to chlorophyll in a green alga Codium fragile
    M Mimuro, S Akimoto, A Murakami, T Sakawa, S Takaichi, Yamazaki, I
    2003, PLANT AND CELL PHYSIOLOGY, 44, S157 - S157, English
    Summary international conference

  • A Nakano, Y Yasuda, T Yamazaki, S Akimoto, Yamazaki, I, H Miyasaka, A Itaya, M Murakami, A Osuka
    May 2001, JOURNAL OF PHYSICAL CHEMISTRY A, 105(20) (20), 4822 - 4833, English
    Book review

  • 酸素発生型光合成生物の蛍光特性の多様性
    三室守, 秋本誠志, 宮下英明, 山崎巌
    04 Aug. 2000, 日本光医学・光生物学会, 22nd, 38, Japanese

  • 藍色細菌Gloeobacter violaceusの特異な蛍光特性
    大久保隆宏, 高田健吾, 秋本誠志, 宮下英明, 山崎巌, 三室守
    May 2000, マリンバイオテクノロジー学会大会講演要旨集, 4th, 74, Japanese

  • Femtosecond Time-Resolved Fluorescence Spectroscopy for Ultrafast Photophysical Processes in Photoresponsive Proteins
    YAMAZAKI Iwao, AKIMOTO Seiji, MIMURO Mamoru
    12 Nov. 1999, レーザー学会研究会報告 = Reports on the Topical meeting of the Laser Society of Japan, 268, 29 - 34, Japanese

  • 原核光合成生物Acaryochloris marinaの光化学系IIにおけるprimary electron donorの解析
    三室守, 秋本誠志, 山崎巌, 宮下英明, 宮地重遠
    26 May 1999, マリンバイオテクノロジー学会大会講演要旨集, 3rd, 78, Japanese

  • Excited State Dynamics of Carotenoid : Determinant of Roles in Biological System
    MIMURO Mamoru, AKIMOTO Seiji
    光化学協会, 23 Dec. 1998, Photochemistry, 29(1) (1), 6 - 13, Japanese

  • Time-Resolved Fluorescence Spectrophotometer Using a Traveling Wave Plate Type Streak Camera
    AKIMOTO Seiji, TAKAHASHI Akira, KINOSHITA Katsuyuki, WATANABE Motoyuki, KOISHI Musubu, YAMAZAKI Iwao
    レ-ザ-学会, 31 May 1996, The Review of laser engineering, 24(5) (5), 609 - 614, Japanese

■ Books And Other Publications
  • "Modification of Energy Distribution Between Photosystems I and II by Spillover Revealed by Time-Resolved Fluorescence Spectroscopy" in "Photosynthesis: molecular approaches to solar energy conversion" (J.-R. Shen, K. Satoh, S.I. Allakhverdiev (eds.))
    M. Yokono, Y. Ueno, S. Akimoto
    Joint work, Springer, 2021

  • "How light-harvesting and energy-transfer processes are modified under different light conditions: studies by time-resolved fluorescence spectroscopy" in: H.J.M. Hou, M.M. Najafpour, G.F. Moore, S.I. Allakhverdiev (eds.), "Photosynthesis: Structures, mech
    S. Akimoto, M. Yokono
    Joint work, Springer, 2017, English
    Scholarly book

  • 「発光の事典（木下修一ら編）」のうち、「解析方法」
    AKIMOTO SEIJI
    Others, 朝倉書店, 2015, Japanese
    Scholarly book

  • 「光合成のエネルギー変換と物質変換（杉浦美羽ら編）」のうち、「カロテノイド色素とキノン」
    AKIMOTO SEIJI
    Others, 化学同人, 2015, Japanese
    Scholarly book

  • 「光化学の事典」（光化学協会編）のうち「葉緑体」「光化学系I」「光化学系II」を執筆
    AKIMOTO SEIJI
    Joint work, 朝倉書店, 2014, Japanese
    Scholarly book

  • Low-frequency dynamics of water: relation to the fluctuation of the solute molecule
    TOMINAGA Keisuke, Jumpei Tayama, Akane Ishihara, Akina Kariya, Mami Takatsuka, Motohiro Banno, Kaoru Ohta, Shinji Saito, Seiji Akimoto
    Others, Proceedings of 3rd International THz-Bio Workshop, 2012, English
    Scholarly book

  • Light adaptation of cyanobacteria probed by time-resolved fluorescence: modification of energy transfer
    Akimoto Seiji, M.Yokono, F.Hamada, A.Teshigahara, S.Aikawa, A.Kondo
    Others, Proceedings of DAE-BRNS Eleventh Biennial Trombay Symposium on Radiation & Photochemistry (TSRP-2012), 2011, English
    Scholarly book

  • 光合成研究法（編集：田中歩）4章2.a. 蛍光
    Akimoto Seiji
    Single work, 低温科学, 2009, Japanese
    General book

  • Photosynthesis. Energy from the Sun, ed. by J. Allen, E. Gantt, J. Golbeck, B. Osmond, Sec. 3 Chap. 26 “Unique optical properties of LHC II isolated from Codium fragile – its correlation to protein environment”
    T.Tsuchiya, T.Tomo, Akimoto Seiji, A.Murakami, dM.Mimuro
    Others, Springer, 2008, English
    Scholarly book

  • Photosynthesis. Energy from the Sun, ed. by J. Allen, E. Gantt, J. Golbeck, B. Osmond, Sec. 3 Chap. 20 “Ultrafast relaxation dynamics of a keto-carotenoid, siphonaxanthin, probed by time-resolved fluorescence”
    Akimoto Seiji, M.Yokono, M.Higuchi, A.Murakami, S.Takaichi, dM.Mimuro
    Others, Springer, 2008, English
    Scholarly book

  • Photosynthesis. Energy from the Sun, ed. by J. Allen, E. Gantt, J. Golbeck, B. Osmond, Sec. 3 Chap. 15 “Excitation energy transfer in PS I of the cyanobacterium Gloeobacter violaceus PCC 7421 that lacks the long-wavelength form of chlorophyll a”
    M.Mimuro, M.Higuchi, H.Inoue, M.Yokono, T.Tsuchiya, H.Miyashita, Akimoto Seiji
    Others, Springer, 2008, English
    Scholarly book

  • Photosynthesis. Energy from the Sun, ed. by J. Allen, E. Gantt, J. Golbeck, B. Osmond, Sec. 2 Chap. 45 “Identification of the special pair and ChlZ of photosystem II in Acaryochloris marina”
    T.Tomo, T.Okubo, Akimoto Seiji, H.Miyashita, T.Tsuchiya, T.Noguchi, dM.Mimuro
    Others, Springer, 2008, English
    Scholarly book

  • Photosynthesis. Energy from the Sun, ed. by J. Allen, E. Gantt, J. Golbeck, B. Osmond, Sec. 15 Chap. 9 “Simulation of excitation energy transfer within the PSI-LHCI/II supercomplex from Chlamydomonas reinhardtii”
    M.Yokono, M.Iwai, Akimoto Seiji, dJ.Minagawa
    Others, Springer, 2008, English
    Scholarly book

  • Photoinduced electron transfer and aggregation behaviour of zinc porphyrin-b-cyclodextrin conjugates
    T.Kiba, H.Suzuki, K.Hosokawa, Akimoto Seiji, T.Kakuchi, dS.Sato
    Others, Proceedings of the 14th International Cyclodextrins Symposium, 2008, English
    Scholarly book

■ Lectures, oral presentations, etc.
  • シアノバクテリア Synechococcus leopoliensis のエネルギー移動における光質応答
    倉地秀鷹, 酒井希, 藍川晋平, 秋本誠志
    Mar. 2025, Japanese
    Poster presentation

  • Acclimation of white-light-adapted Halomicronema hongdechloris to different light qualities
    Zhe Wang, Toshiyuki Shinoda, Tatsuya Tomo, Seiji Akimoto
    The 66th Annual Meeting of the Japanese Society of Plant Physiologists, Mar. 2025, English
    Poster presentation

  • Roles of Minor Red-Shifted Chlorophyll a in a Unicellular Green Alga Neochloris sp. Biwa 5-2
    Fei Wang, Seiji Akimoto, Hideaki Miyashita
    The 66th Annual Meeting of the Japanese Society of Plant Physiologists, Mar. 2025, English

  • 鉄 / 銅欠乏条件が微細藻類の光合成初期過程に与える影響
    酒井希, 古谷実佑, 藍川晋平, 秋本誠志
    第66回日本植物生理学会年会, Mar. 2025, Japanese

  • 鉄欠乏 / 過剰条件が微細藻類のエネルギー移動に与える影響に関する時間分解蛍光測定
    酒井希, 古谷実佑, 藍川晋平, 秋本誠志
    第66回日本植物生理学会年会, Mar. 2025, Japanese

  • Physiological function and assembly of the large PSI-LHCI supercomplex in the diatom Chaetoceros gracilis
    Jian Xing, Minoru Kumazawa, Seiji Akimoto, Shoko Tsuji, Noriko Ishikawa, Kentaro Ifuku
    The 66th Annual Meeting of the Japanese Society of Plant Physiologists, Mar. 2025, English

  • ツノケイソウにおけるLhcxタンパク質を介した光防御と強光順化の統合
    熊沢穣, 秋本誠志, 高林厚史, 辻祥子, 長谷川葉月, 櫻井敦, 今村壮輔, 石川規子, 井上, 菓子野, 名津子, 菓子野康浩, 伊福健太郎
    第66回日本植物生理学会年会, Mar. 2025, Japanese
    Poster presentation

  • 海洋珪藻 Chaetoceros gracilis の光とCO2 に応答した集光性色素タンパク質のリモデリング
    中村翠, 熊沢穣, 長尾遼, 辻祥子, 鈴木健裕, 石川規子, 堂前直, 秋本誠志, 伊福健太郎
    第66回日本植物生理学会年会, Mar. 2025, Japanese

  • Responses of light-harvesting and energy-transfer processes in typical cyanobacteria to light qualities
    Seiji Akimoto
    Photosynthesis and Hydrogen Energy Research for Sustainability – 2024, Oct. 2024, English
    [Invited]
    Invited oral presentation

  • A Light-Harvesting Protein for Adaptation in Specific Light and CO2 Conditions in the Marine Diatom Chaetoceros Gracilis
    Midori NAKAMURA, Minoru KUMAZAWA, Ryo NAGAO, Shoko TSUJI, Takehiro SUZUKI, Noriko ISHIKAWA, Naoshi DOHMAE, Seiji AKIMOTO, Kentaro IFUKU
    Photosynthesis and Hydrogen Energy Research for Sustainability – 2024, English
    Poster presentation

  • Biochemical and Spectroscopic Insights into the PSI-LHCI Supercomplex of the Diatom Chaetoceros Gracilis Lacking a Single LHCI
    Jian XING, Minoru KUMAZAWA, Seiji AKIMOTO, Shoko TSUJI, Noriko ISHIKAWA, Kentaro Ifuku
    Photosynthesis and Hydrogen Energy Research for Sustainability – 2024, English

  • 集光性色素タンパク質FCPにみられるエネルギー移動と光環境応答
    秋本 誠志
    光合成初期過程の高速ダイナミクスに関する研究会, Oct. 2024, Japanese
    [Invited]

  • Characterization of FCP responding to light and CO2 conditions in marinediatom Chaetoceros gracilis
    Midori Nakamura, Minoru Kumazawa, Ryo Nagao, Shoko Tsuji, Takehiro Suzuki, Noriko Ishikawa, Naoshi Dohmae, Seji Akimoto, Kentaro Ifuku
    2nd Asia-Oceania International Congress on Photosynthesis (AOICP), Sep. 2024, English

  • Revisiting the early light-induced protein hypothesis in the sustained thermal dissipation mechanism in yew leaves
    Zihao Ye, Mina Sawada, Makiko Iwasa, Ryo Moriyama, Debayan Dey, Miyu Furutani, Mitsutoshi Kitao, Toshihiko Hara, Ayumi Tanaka, Junko Kishimoto, Makio Yokono, Seiji Akimoto, Atsushi Takabayashi, Ryouichi Tanaka
    2nd Asia-Oceania International Congress on Photosynthesis (AOICP), Sep. 2024, English

  • Configuration of antenna assembly, electron transport, and excitation energy transfer within different FCPI-deficient strains of diatom Chaetoceros gracilis
    Jian Xing, Minoru Kumazawa, Seiji Akimoto, Shoko Tsuji, Noriko Ishikawa, Kentaro Ifuku
    2nd Asia-Oceania International Congress on Photosynthesis (AOICP), Sep. 2024, English

  • Characterization of the light-harvesting 1 reaction center complexes from psychrophilic purple nonsulfur bacteria
    Kazuki Inada, Seiji Akimoto, Shinji Takenaka, Michael T. Madigan, Zheng-Yu Wang-Otomo, Yukihiro Kimura
    2nd Asia-Oceania International Congress on Photosynthesis (AOICP), Sep. 2024, English
    [Invited]

  • 好冷性紅⾊光合成細菌における光捕集 1 反応中⼼複合体の特性解析
    稲田 一輝, 秋本 誠志, 竹中 慎治, Michael, T. Madigan, 大友 征宇, 木村 行宏
    光合成セミナー2024, Jun. 2024, Japanese
    Poster presentation

  • 遠⾚光に馴化させた Ha lomicronem a hongdechlorisの単⾊光応答
    王 一鵬, 王 哲, 篠田 稔行, 鞆 達也, 秋本 誠志
    光合成セミナー2024, Jun. 2024, Japanese
    Poster presentation

  • シアノバクテリアSynechococcus leopoliensis の光合成初期過程に 鉄イオン濃度が与える影響
    酒井 希, 藍川 晋平, 秋本 誠志
    光合成セミナー2024, Jun. 2024, Japanese
    Poster presentation

  • シアノバクテリアSynechococcus とSynechocystis に見られる光質応答の違い
    秋本 誠志
    光合成セミナー2024, Japanese
    Oral presentation

  • Comparison of energy transfer processes between two Acaryochloris marina strains in response to different light qualities
    Zhe Wang, Miyu Furutani, Ryo Nagao, Yoshifumi Ueno, Reona Toyofuku, Tatsuya Tomo, Seiji Akimoto
    第65回日本植物生理学会年会, Mar. 2024, Japanese
    Poster presentation

  • マイクロ秒領域における光合成系の励起緩和過程
    古谷 実祐, 秋本 誠志
    第65回日本植物生理学会年会, Mar. 2024, Japanese
    Poster presentation

  • 鉄欠乏/過剰条件が緑藻の光合成初期過程に与える影響のグローバル解析による評価,
    酒井 希, 古谷 実祐, 藍川 晋平, 秋本 誠志
    第65回日本植物生理学会年会, Mar. 2024, Japanese
    Poster presentation

  • 光化学系 I の低エネルギークロロフィルによる消光
    秋本 誠志, 松坂 紘斗, 古谷 実祐, 長尾 遼, 松永 恭子, 鞆 達也
    第65回日本植物生理学会年会, Mar. 2024, Japanese
    Oral presentation

  • Diversity of responses to different light conditions in excitation energy transfer of cyanobacteria
    S. Akimoto
    Trombay Symposium on Radiation and Photochemistry (TSRP-2024), Jan. 2024, English
    [Invited]
    Invited oral presentation

  • クロロフィルc の電子励起状態に関する考察
    水村 景太, 鞆 達也, 秋本 誠志
    若手フロンティア研究会2023, Dec. 2023, Japanese
    Poster presentation

  • クロレラの光合成初期過程に鉄イオン濃度が与える影響
    酒井 希, 藍川 晋平, 秋本 誠志
    第3回先端バイオ工学研究センター成果発表会, Oct. 2023, Japanese
    Poster presentation

  • 時間分解分光法による灰色藻Cyanophora pradoxa の光合成初期過程に対する鉄環境の影響の調査
    酒井 希, 古谷 実祐, 植野 嘉文, 藍川 晋平, 秋本 誠志
    第17回分子科学討論会, Sep. 2023, Japanese
    Poster presentation

  • 鉄濃度が緑藻Chlorella variabilis の光合成初期過程に与える影響 –分光学的手法による調査–
    酒井 希, 藍川 晋平, 秋本 誠志
    光合成セミナー2023, Jun. 2023, Japanese
    Poster presentation

  • サブマイクロ秒領域における光合成系の時間分解測定
    古谷 実祐, 秋本 誠志
    Jun. 2023, Japanese
    Poster presentation

  • 遅延蛍光測定による光化学系の光質応答に関する考察
    光合成セミナー2023, Jun. 2023, Japanese
    Oral presentation

  • 遠赤色光条件下における2種類のEuglena grasilis の応答の違い
    Yuki Sorihashi, Yoshifumi Ueno, Jian-Ren Shen, Ryo Nagao, Seiji Akimoto
    第64回日本植物生理学会年会, Mar. 2023
    Others

  • Regulation of antenna and energy transfer in photosystems of Acaryochloris marina in response to different light qualities
    王 哲, 植野 嘉文, 沈 建仁, 長尾 遼, 豊福 玲於奈, 鞆 達也, 秋本 誠志
    第64回日本植物生理学会年会, Mar. 2023
    Others

  • クロロフィルd 型シアノバクテリアの光質応答とその多様性
    王 哲, 植野 嘉文, 沈 建仁, 長尾 遼, 豊福 玲於奈, 鞆 達也, 秋本 誠志
    第11回サイエンスフロンティア研究発表会, Oct. 2022
    Poster presentation

  • 種々のケトカロテノイドにおける励起緩和ダイナミクス
    秋本誠志
    第34回カロテノイド研究談話会, Sep. 2022
    [Invited]
    Invited oral presentation

  • フィコビリタンパク質を持たないアカリオクロリスの光質応答
    王 哲, 植野 嘉文, 沈 建仁, 長尾 遼, 豊福 玲於奈, 鞆 達也, 秋本 誠志
    光合成セミナー2022：反応中心と色素系の多様性, Jun. 2022
    Others

  • 2 種類の Euglena gracilis における光質応答の違い
    反橋勇貴, 植野嘉文, 沈建仁, 長尾遼, 秋本誠志
    光合成セミナー2022：反応中心と色素系の多様性, Jun. 2022
    Others

  • 灰色藻Cyanophora pradoxaにおけるステート遷移の分子機構
    植野 嘉文, 秋本 誠志
    光合成セミナー2022：反応中心と色素系の多様性, Jun. 2022
    Others

  • Euglena gracilis strain Z の励起エネルギー移動過程における培養光光質応答
    反橋勇貴, 植野嘉文, 坂本月, 沈建仁, 長尾遼, 秋本誠志
    第63回日本植物生理学会, Mar. 2022
    Poster presentation

  • 2 種類の Arcaryochloris marina の光質応答
    王哲, 植野嘉文, 横野牧生, 沈建仁, 長尾遼, 豊福玲於奈, 鞆達也, 秋本誠志
    第63回日本植物生理学会, Mar. 2022
    Poster presentation

  • 異なる変動光条件に順化した緑藻 Chlorella variabilis における非光化学消光に伴う光捕集機能の制御
    植野嘉文, 藍川晋平, 秋本誠志
    第63回日本植物生理学会, Mar. 2022
    Poster presentation

  • 光合成系カロテノイドの機能と励起緩和ダイナミクス
    日本分光学会関西支部講演会, Mar. 2022, Japanese
    [Invited]

  • Excitation relaxation dynamics and photosynthetic functions of carotenoids with different structures
    Seiji Akimoto
    16th DAE-BRNS Biennial Trombay Symposium on Radiation & Photochemistry, Jan. 2022, English
    [Invited]
    Invited oral presentation

  • Euglena gracilis strain Z の培養光光質応答
    反橋勇貴, 植野嘉文, 坂本月, 沈建人, 長尾遼, 秋本誠志
    若手フロンティア研究会2021, Dec. 2021, Japanese

  • Excitation Relaxation Dynamics of Carotenoids Found in Photosynthetic Organisms
    Seiji Akimoto
    Pacifichem 2021, Dec. 2021, English
    [Invited]
    Invited oral presentation

  • Arthrospira platensis のred Chl について
    松永 恭子, 本多 未来, 長尾 遼, 沈 建仁, 秋本 誠志, 鞆 達也
    日本生物物理学会年会

  • 異なる光強度で培養された緑藻Chlorella variabilisにおける光エネルギー調節機構に関する研究
    植野嘉文, 藍川晋平, 秋本誠志
    光合成セミナー2021, Jun. 2021

  • パターン化人工膜へのチラコイド膜再構成技術の開発
    楠祐佳, 高木大輔, 秋本誠志, 森垣憲一
    光合成セミナー2021, Jun. 2021

  • ３つの好極限性を有する紅色光合成細菌Halorhodospira halochlorisの特性解析
    中田和菜, 能島紳吾, 山下琢也, 秋本誠志, 小林正幸, 竹中慎治, Madigan, M.T, 大友征宇, 木村行宏
    光合成セミナー2021, Jun. 2021

  • ユーグレナの励起エネルギー移動過程における光質応答
    反橋勇貴, 植野嘉文, 横野牧生, 加藤香穂, 沈建仁, 長尾遼, 秋本誠志
    光合成セミナー2021, Jun. 2021

  • 摂動を与えたフコキサンチンクロロフィルタンパク質の励起緩和ダイナミクス
    長尾遼, 横野牧生, 沈建仁, 秋本誠志
    光合成セミナー2021, Jun. 2021
    Oral presentation

  • 種々の光化学系I複合体に見られる低エネルギークロロフィルの機能解明
    松坂紘斗, 長尾遼, 沈建仁, 本田未来, 鞆達也, 秋本誠志
    光合成セミナー2021, Jun. 2021
    Oral presentation

  • ハマサンゴの骨格から分離した糸状緑藻Phaeophila dendroides による遠赤色光の利用
    大波 千恵子, 西堀 洋平, 植野 嘉文, 須田 彰一郎, 神川 龍馬, 秋本 誠志, 宮下 英明
    日本藻類学会第45回大会, Mar. 2021

  • 光質に対するEuglena gracilis の励起エネルギー移動過程の応答
    反橋 勇貴, 植野 嘉文, 横野 牧生, 加藤 香穂, 沈 建仁, 長尾 遼, 秋本 誠志
    第62回日本植物生理学会年会, Mar. 2021

  • 珪藻における光捕集・エネルギー移動過程の変動赤色光への応答
    田邊 みゆき, 植野 嘉文, 横野 牧生, 沈 建仁, 長尾 遼, 秋本 誠志
    第62回日本植物生理学会年会, Mar. 2021

  • 時間分解蛍光分光法によるアカリオクロリスの光質応答に関する研究
    王 哲, 植野 嘉文, 横野 牧生, 豊福 玲於奈, 鞆 達也, 秋本 誠志
    第62回日本植物生理学会年会, Mar. 2021

  • Synechocystis sp. PCC 6803のΔndhD1/D2 株を用いたレドックスバランス感知フィコビリソーム分解制御機構の解析
    豊島 正和, 阪田 真澄, 山本 千晶, 植野 嘉文, 戸谷 吉博, 秋本 誠志, 清水 浩
    Mar. 2021

  • 変動光に対するEuglena gracilis のエネルギー移動過程の応答
    田邊 みゆき, 植野 嘉文, 横野 牧生, 加藤 香穂, 沈 建仁, 長尾 遼, 秋本 誠志
    第62回日本植物生理学会年会, Mar. 2021

  • 遠赤色光下で真核藻類が蓄積する低エネルギー集光性複合体が光合成初期過程に与える影響,
    松坂 紘斗, 植野 嘉文, 王 菲, 宮下 英明, 沈 建仁, 長尾 遼, 横野 牧生, 秋本 誠志
    第62回日本植物生理学会年会, Mar. 2021

  • 異なる光強度に順化した緑色微細藻における非光化学消光に伴う光捕集機能の調節
    植野 嘉文, 藍川 晋平, 秋本 誠志
    第62回日本植物生理学会年会, Mar. 2021

  • 緑色植物の光化学系I–II超複合体
    横野 牧生, 高林 厚史, 秋本 誠志
    第23回植物オルガネラワークショップ, Mar. 2021, Japanese, Domestic conference
    [Invited]
    Nominated symposium

  • Charge Transfer Dynamics of 9-Arylcarbazole Studied by Femtosecond Transient Absorption Spectroscopy
    Kazuya Takamoto, Yoshifumi Ueno, Kaoru Ohta, Seiji Akimoto, Ryosuke Matsubara, Keisuke Tominaga
    Asian Spectroscopy Conference 2020, 2020, English
    Poster presentation

  • クロロフィル f をもつ光化学系I複合体の構造
    篠田 稔行, 加藤 公児, 長尾 遼, 秋本 誠志, 沈 建仁, 秋田 総理, 宮崎 直幸, 鞆 達也
    第58回日本生物物理学会, Sep. 2020

  • 蛍光分光法による微細藻の光エネルギー調整機構に関する研究
    植野 嘉文, 秋本 誠志
    2020年web光化学討論会, Sep. 2020

  • 光化学系I–鉄欠乏ストレス誘導タンパク質超複合体の構造解析
    秋田 総理, 長尾 遼, 加藤 公児, 中島 芳樹, 横野 牧生, 植野 嘉文, 鈴木 健裕, 堂前 直, 沈 建仁, 秋本 誠志, 宮崎 直幸
    日本農芸化学会2020年度大会, Mar. 2020, Domestic conference

  • 13C代謝フラックス解析を用いたシアノバクテリアにおける光化学系からのATP/NADPH 生産速度の推定
    山本 千晶, 北村 さやか, 豊島 正和, 植野 嘉文, 戸谷 吉博, 秋本 誠志, 清水 浩
    第61回日本植物生理学会年会, Mar. 2020, Domestic conference
    Poster presentation

  • Spectral changes of Acaryochloris marina in response to different light qualities
    Z. Wang, Y. Ueno, , R. Toyofuku, T. Tomo, S. Akimoto
    第61回日本植物生理学会年会, Mar. 2020, Domestic conference
    Poster presentation

  • 異なる周期を持つ変動光に対する珪藻2種のエネルギー移動過程の応答
    田邊 みゆき, 植野 嘉文, 横野 牧生, 沈 建仁, 長尾 遼, 秋本 誠志
    第61回日本植物生理学会年会, Mar. 2020, Domestic conference
    Poster presentation

  • BAシミュレーションによる異なる波長の光照射下におけるSynechocystis sp. PCC 6803 の光合成電子伝達経路の選択的使用の解明
    豊島 正和, 山本 千晶, 植野 嘉文, 戸谷 吉博, 秋本 誠志, 清水 浩
    第61回日本植物生理学会年会, Mar. 2020, Domestic conference
    Poster presentation

  • 長波長型クロロフィルa による光合成初期過程の遠赤色光への応答
    松坂 紘斗, 植野 嘉文, 沈 建仁, 長尾 遼, Fei Wang, 宮下 英明, 秋本 誠志
    第61回日本植物生理学会年会, Mar. 2020, Domestic conference
    Poster presentation

  • クライオ電顕によるPSI-isiA超複合体の構造解析
    秋田 総理, 長尾 遼, 加藤 公児, 中島 芳樹, 横野 牧生, 植野 嘉文, 鈴木 健裕, 堂前 直, 沈 建仁, 秋本 誠志, 宮崎 直幸
    第61回日本植物生理学会年会, Mar. 2020, Domestic conference
    Poster presentation

  • アナベナ由来光化学系I四量体のクライオ電顕構造解析
    加藤 公児, 長尾 遼, 蔣 天翼, 植野 嘉文, 横野 牧生, 陳 兆傑, 渡辺 麻衣, 池内 昌彦, 沈 建仁, 秋本 誠志, 宮崎 直幸, 秋田 総理
    第61回日本植物生理学会年会, Mar. 2020, Domestic conference
    Poster presentation

  • 蛍光分光法を用いた灰色藻Cyanophora paradoxa の短期光環境応答
    植野 嘉文, 秋本 誠志
    第61回日本植物生理学会年会, Mar. 2020, Domestic conference
    Oral presentation

  • クロロフィルf をもつ光化学系 I 複合体の構造および分光的特性について
    篠田 稔行, 加藤 公児, 長尾 遼, 秋本 誠志, 沈 建仁, 秋田 総理, 宮崎 直幸, 鞆 達也
    第61回日本植物生理学会年会, Mar. 2020, Domestic conference
    Oral presentation

  • 珪藻PSI-FCPI複合体のクライオ電顕構造解析
    長尾 遼, 加藤 公児, 伊福 健太郎, 鈴木 健裕, 熊沢 穣, 内山 郁夫, 菓子野 康浩, 堂前 直, 秋本 誠志, 沈 建仁, 宮崎 直幸, 秋田 総理
    第61回日本植物生理学会年会, Mar. 2020, Domestic conference
    Oral presentation

  • Light-harvesting and energy-transfer processes by low-energy chlorophylls in phtosynthesis
    S. Akimoto, Y. Ueno, M. Yokono, S.I. Allakhverdiev, T. Tomo, J.R. Shen, R. Nagao
    Trombay Symposium on Radiation and Photochemistry, Jan. 2020, International conference, Co-authored internationally
    [Invited]
    Invited oral presentation

  • 環境ストレスに対する植物の応答
    講演会（内蒙古医科大学、中国）, Dec. 2019, International conference
    [Invited]
    Public discourse

  • Adaptation of energy-transfer processes in diatoms to environmental light conditions
    S. Akimoto, Y. Ueno, M. Yokono, J.-R. Shen, R. Nagao
    3rd International Solar Fuels Conference/International Conferrence on Artificial Photosynthesis-2019, Nov. 2019, International conference
    Poster presentation

  • Cryo-EM structure of the diatom PSII–FCPII: Insights into the evolutionary development of light-harvesting complexes
    R. Nagao, F. Akita, K. Kato, T. Suzuki, K Ifuku, I. Uchiyama, Y. Kashino, N. Dohmae, S. Akimoto, N. Miyazaki, J.-R. Shen
    3rd International Solar Fuels Conference/International Conferrence on Artificial Photosynthesis-2019, Nov. 2019, International conference
    Poster presentation

  • Spectroscopic properties of novel red-shifted fucoxanthin chlorophyll a/c-binding protein complexes
    Y. Ueno, R. Nagao, J.-R. Shen, S. Akimoto
    3rd International Solar Fuels Conference/International Conferrence on Artificial Photosynthesis-2019, Nov. 2019
    Oral presentation

  • Modification of light-harvesting and energy-transfer processes in photosynthetic organisms under different environmetal conditions
    S. Akimoto
    International workshop on frontier science and technology for solar energy conversion, Nov. 2019, International conference
    [Invited]
    Invited oral presentation

  • Dual photoprotection mechanisms during CO2-dependent photosynthesis in the green alga Chlorella variabilis
    Y. Ueno, G. Shimakawa, S. Aikawa, C. Miyake, S. Akimoto
    日米二国間セミナー, Oct. 2019, International conference
    Poster presentation

  • FBA simulation of photosynthetic electron flow of Synechocystis sp. PCC 6803 under different spectral light condition
    M. Toyoshima, C. Yamamoto, Y. Ueno, Y. Toya, S. Akimoto, H. Shimizu
    日米二国間セミナー, Oct. 2019, International conference
    Poster presentation

  • Structua basis of energy harvesting and dissipation in diatom PSII-FCPII
    R. Nagao, F. Akita, K. Kato, T. Suzuki, K. Ifuku, I. Uchiyama, Y. Kashino, N. Dohmae, S. Akimoto, N. Miyazaki, J.-R. Shen
    The 9th Asia and Oceania Conference on Photobiology, Sep. 2019, International conference
    Poster presentation

  • Responsesn of energy-transfer processes in diatoms Chaetoceros gracilis and Phaeodactylum tricornutum to fluctuating light, ~effects of low/high- and low/dark-fluctuations~
    M. Tanabe, Y. Ueno, M. Yokono, J.-R. Shen, Ryo Nagao, S. Akimoto
    The 9th Asia and Oceania Conference on Photobiology, Sep. 2019, International conference
    Poster presentation

  • Modification of excitation energy-transfer processes of the primary symbiotic algae grown under different light qualities
    Y. Ueno, S. Aikawa, A. Kondo, S. Akimoto
    The 9th Asia and Oceania Conference on Photobiology, Sep. 2019, International conference
    Poster presentation

  • Changes in light-harvesting and energy-transfer processes of diatoms in responce to different light qualities
    S. Akimoto, Y. Ueno, M. Yokono, J.-R. Shen, R. Nagao
    The 9th Asia and Oceania Conference on Photobiology, Sep. 2019, International conference
    [Invited]
    Invited oral presentation

  • Molecular geometries and motions driving quintet multiexcitons via singlet fissions
    ○Yasuhiro Kobori, Hiroki Nagashima, Shuhei Kawaoka, Seiji Akimoto, Takashi Tachikawa, Yasunori Matsui, Hiroshi Ikeda
    16th International Symposium on Spin and Magnetic Field Effects in Chemistry and Related Phenomena, Aug. 2019, English, Saint Petersburg, Russia, International conference
    Oral presentation

  • 変動光に対する珪藻中のエネルギー移動の応答
    田邊 みゆき, 植野 嘉文, 横野 牧生, 沈 建仁, 長尾 遼, AKIMOTO SEIJI
    第27回「光合成セミナー2019」, Jul. 2019, Japanese, 大阪大学理学研究科, Domestic conference
    Oral presentation

  • 珪藻に見られる低エネルギー型アンテナ色素タンパク質複合体
    秋本 誠志, 植野 嘉文, 横野 牧生, 沈 建仁, 長尾 遼
    第27回「光合成セミナー2019」, Jul. 2019, Japanese, 大阪大学理学研究科, Domestic conference
    Oral presentation

  • 珪藻Chaetoceros gracilisにおける赤色光誘導アンテナ色素タンパク質複合体の分光特性
    植野 嘉文, 長尾 遼, 沈 建仁, AKIMOTO SEIJI
    第27回「光合成セミナー2019」, Jul. 2019, Japanese, 大阪大学理学研究科, Domestic conference
    Poster presentation

  • Chl a型およびChl d型光化学系IIにおける初期電子受容体Pheophytin aの分光分析
    豊福 玲於奈, AKIMOTO SEIJI, 鞆 達也
    第27回「光合成セミナー2019」, Jul. 2019, Japanese, 大阪大学理学研究科, Domestic conference
    Poster presentation

  • Adaptation of light-harvesting functions of the glaucophyte Cyanophora paradoxa under different light conditions
    Y. Ueno, S. Akimoto
    Photosynthesis and Hydrogen Energy Research for Sustainability – 2019, Jun. 2019, International conference
    Poster presentation

  • Responses of energy-transfer processes in diatoms to fluctuating light
    M. Tanabe, Y. Ueno, M. Yokono, J.-R. Shen, R. Nabgao, S. Akimoto
    Photosynthesis and Hydrogen Energy Research for Sustainability – 2019, Jun. 2019, International conference
    Poster presentation

  • Modification of light-harvesting and energy-transfer processes in diatoms under different light conditions
    S. Akimoto, Y. Ueno, M. Yokono, J.-R. Shen, R. Nagao
    Photosynthesis and Hydrogen Energy Research for Sustainability – 2019, Jun. 2019, International conference
    Oral presentation

  • Structual basis of energy harvesting and dissipation in diatom PSII-FCPII complexes revealed by cryo-electron microscopy
    R. Nagao, F. Akita, K. Kato, T. Suzuki, K. Ifuku, I. Uchiyama, Y. Kashino, N. Dohmae, S. Akimoto, N. Miyazaki, J.-R. Shen
    Photosynthesis and Hydrogen Energy Research for Sustainability – 2019, Jun. 2019, International conference
    Oral presentation

  • Characterization of a new carotenoid in a kind of land plants
    R. Nagayoshi, S. Akimoto, H. Ohta, T. Tomo
    Photosynthesis and Hydrogen Energy Research for Sustainability – 2019, Jun. 2019, International conference
    Poster presentation

  • Analysis of energy transfer pathways in cyanobacterium during the process of the chlorophyll f accumulation
    T. Shinoda, S. Akimoto, M. Chen, S.I. Allakhverdiev, T. Tomo
    Photosynthesis and Hydrogen Energy Research for Sustainability – 2019, Jun. 2019
    Invited oral presentation

  • クライオ電子顕微鏡を用いたPSI–IsiA超複合体の構造解析
    秋田 総理, 長尾 遼, 加藤 公児, 中島 芳樹, 秋本 誠志, 沈 建仁, 宮崎 直幸
    日本顕微鏡学会第75回学術講演会, Jun. 2019

  • 珪藻の光化学系II–集光性タンパク質FCPIIのクライオ電顕構造解析
    長尾 遼, 秋田 総理, 加藤 公児, 鈴木 健裕, 伊福 健太郎, 内山 郁夫, 菓子野 康浩, 堂前 直, 秋本 誠志, 宮崎 直幸, 沈 建仁
    日本顕微鏡学会第75回学術講演会, Jun. 2019
    Oral presentation

  • Molecular Geometries and Motions Drive Quintet Multiexcitons via Singlet Fissions
    ○Yasuhiro Kobori, Hiroki Nagashima, Shuhei Kawaoka, Seiji Akimoto, Takashi Tachikawa, Yasunori Matsui, Hiroshi Ikeda
    6th Awaji International Workshop on “Electron Spin Science & Technology: Biological and Materials Science Oriented Applications” (6th AWEST 2019), Jun. 2019, English, Awaji Yumebutai International Conference Center, International conference
    Oral presentation

  • 変動光に対する珪藻Cheotoceros gracilis とPhaeodactylum tricornutum の応答
    田邊 みゆき, 植野 嘉文, 横野 牧生, 沈 建仁, 長尾 遼, 秋本 誠志
    第10回日本光合成学会年会, May 2019
    Poster presentation

  • 灰色藻Cyanophora paradoxa の光捕集機能における培養光質と光量の影響
    植野 嘉文, 秋本 誠志
    第10回日本光合成学会年会, May 2019, Japanese
    Poster presentation

  • 時間分解蛍光分光法を用いた灰色藻Cyanophora paradoxaの長期光環境応答
    植野 嘉文, AKIMOTO SEIJI
    第60回日本植物生理学会年会, Mar. 2019, Japanese, 名古屋大学東山キャンパス, Domestic conference
    Poster presentation

  • 珪藻PSII-FCPII 複合体のクライオ電顕構造解析
    長尾 遼, 秋田 総理, 加藤 公児, 鈴木 健裕, 伊福 健太郎, 内山 郁夫, 菓子野 康浩, 堂前 直, AKIMOTO SEIJI, 宮崎 直幸, 沈 建仁
    第60回日本植物生理学会年会, Mar. 2019, Japanese, 名古屋大学東山キャンパス, Domestic conference
    Oral presentation

  • クロロフィル f 蓄積過程の光化学系I 複合体におけるエネルギー移動経路の確立
    篠田 稔行, 新井 啓史, AKIMOTO SEIJI, 鞆 達也
    第60回日本植物生理学会年会, Mar. 2019, Japanese, 名古屋大学東山キャンパス, Domestic conference
    Oral presentation

  • クロロフィル f 蓄積過程のシアノバクテリアにおけるエネルギー移動経路の確立
    篠田 稔行, 新井 啓史, 田伏 廣輝, AKIMOTO SEIJI, 鞆 達也
    第60回日本植物生理学会年会, Mar. 2019, Japanese, 名古屋大学東山キャンパス, Domestic conference
    Oral presentation

  • アンテナ機能を持ったカロテノイドの励起緩和ダイナミクス
    加賀谷 航平, 長尾 遼, 沈 建仁, 豊福 玲於奈, 鞆 達也, AKIMOTO SEIJI
    第60回日本植物生理学会年会, Mar. 2019, Japanese, 名古屋大学東山キャンパス, Domestic conference
    Oral presentation

  • 羽状目珪藻Phaeodactylum tricornutumにおける光捕集機能の培養光質依存性
    植野 嘉文, 岡 久美子, 長尾 遼, 横野 牧生, 沈 建仁, AKIMOTO SEIJI
    神戸大学 研究基盤センター若手フロンティア研究会2018, Dec. 2018, Japanese, 神戸大学百年記念館, Domestic conference
    Poster presentation

  • 長い共役を持ったケトカロテノイドの励起緩和ダイナミクス
    加賀谷 航平, 山野 由美子, 高市 真一, AKIMOTO SEIJI
    2018年光化学討論会, Sep. 2018, Japanese, 関西学院大学・上ケ原キャンパス, Domestic conference
    Poster presentation

  • 時間分解EPRによる一重項分裂反応から生じた三重項励起子対のダイナミクスの解析
    長嶋 宏樹, 河岡 秀平, AKIMOTO SEIJI, TACHIKAWA TAKASHI, 松井 康哲, 池田 浩, KOBORI YASUHIRO
    第12回分子科学討論会2018, Sep. 2018, Japanese, 福岡国際会議場, Domestic conference
    Oral presentation

  • 光エネルギー利用効率制御の多様性
    AKIMOTO SEIJI
    日本植物学会第82回大会, Sep. 2018, Japanese, 広島国際会議場, Domestic conference
    [Invited]
    Invited oral presentation

  • 蛍光分光法による酸素発生型光合成生物における光エネルギー調節機構に関する研究
    植野 嘉文, 嶋川 銀河, 藍川 晋平, MIYAKE CHIKAHIRO, AKIMOTO SEIJI
    2018年光化学討論会, Sep. 2018, Japanese, 関西学院大学・上ケ原キャンパス, Domestic conference
    Poster presentation

  • TREPR 法によるシングレットフィッションにおける五重項状態の生成機構
    長嶋 宏樹, 河岡 秀平, AKIMOTO SEIJI, TACHIKAWA TAKASHI, 松井 康哲, 池田 浩, KOBORI YASUHIRO
    2018年光化学討論会, Sep. 2018, Japanese, 関西学院大学・上ケ原キャンパス, Domestic conference
    Oral presentation

  • Modification of light-harvesting and energy-transfer processes under different light conditions
    Seiji Akimoto, S. Aikawa, A. Kondo
    1st Asia-Oceania International Congress on Photosynthesis(AOICP2018), Aug. 2018, English, Friendship Hotel in Beijing, International conference
    [Invited]
    Invited oral presentation

  • クライオ電子顕微鏡による珪藻PSII-FCPII複合体の構造解析
    長尾 遼, 秋田 総理, 加藤 公児, 鈴木 健裕, 伊福 健太郎, 内山 郁夫, 菓子野 康浩, 堂前 直, AKIMOTO SEIJI, 宮崎 直幸, 沈 建仁
    光合成セミナー2018：反応中心と色素系の多様性, Jul. 2018, Japanese, 神戸, Domestic conference
    Oral presentation

  • Time-Resolved EPR Study on Singlet Fission and Subsequent Triplet Dissociation Dynamics
    Hiroki Nagashima, Shuhei Kawaoka, Seiji Akimoto, Takashi Tachikawa, Yasunori Matsui, Hiroshi Ikeda, ○Yasuhiro Kobori
    35th International Conference of Photopolymer Science and Technology(ICPST-35), Jun. 2018, English, 幕張メッセ国際会議場, International conference
    [Invited]
    Invited oral presentation

  • チラコイド膜のダイナミクスの違いは PSI-PSII超複合体の構造に影響を与えうる
    横野 牧生, UCHIDA HIROKO, 高林 厚史, 植野 嘉文, AKIMOTO SEIJI, MURAKAMI AKIO
    第9回日本光合成学会, May 2018, Japanese, 東北大学, Domestic conference
    [Invited]
    Invited oral presentation

  • 緑藻クラミドモナスにおけるLHCSR1依存の蛍光の消光はLHCIIからPSIへの励起移動により引き起こされる
    小菅 晃太郎, 得津 隆太郎, Kim Eunchul, 秋本 誠志, 横野 牧生, 植野 嘉文, 皆川 純
    第59回日本植物生理学会年会, Mar. 2018, Japanese, Domestic conference
    Oral presentation

  • 長波長型色素を結合した光化学系エネルギー移動の解析
    篠田 稔行, 田伏 廣輝, 新井 啓史, 秋本 誠志, 鞆 達也
    第7回日本生物物理学会関東支部会, Mar. 2018, Japanese, Domestic conference
    Oral presentation

  • 集光性フコキサンチンタンパク質と光化学系Iコアとの相互作用,
    長尾 遼, 植野 嘉文, 秋本 誠志, 秋田 総理, 沈 建仁
    第59回日本植物生理学会年会, Mar. 2018, Japanese, Domestic conference
    Poster presentation

  • 集光アンテナ装置LHCIIのリン酸化は光化学系間のスピルオーバーを制御する
    得津 隆太郎, Eunchul Kim, 秋本 誠志, 鎌田 このみ, 渡邉 顕正, 大西 紀和, 皆川 純
    第59回日本植物生理学会年会, Mar. 2018, Japanese, Domestic conference
    Poster presentation

  • 異なる色の光で培養されたシアノバクテリアにおけるエネルギー移動過程の比較
    藤本 かおり, 藍川 晋平, KONDO AKIHIKO, 秋本 誠志
    第59回日本植物生理学会年会, Mar. 2018, Japanese, Domestic conference
    Poster presentation

  • ヒメツリガネゴケのPSI-PSII超複合体の解析
    古川 亮, 横野 牧生, 秋本 誠志, 藤田 知道, 高林 厚史, 田中 歩
    第59回日本植物生理学会年会, Mar. 2018, Japanese, Domestic conference
    Oral presentation

  • ジアトキサンチンの励起緩和ダイナミクス
    加賀谷 航平, 長尾 遼, 沈 建仁, 秋本 誠志
    第59回日本植物生理学会年会, Mar. 2018, Japanese, Domestic conference
    Poster presentation

  • クロロフィル d型光化学系II反応中心の色素励起状態エネルギーの解析
    豊福 玲於奈, 秋本 誠志, 篠田 稔行, 鞆達也
    日本物理学会 第73回年次大会, Mar. 2018, Japanese, Domestic conference
    Poster presentation

  • PSI-NPQ in higher plants
    ○Makio Yokono, Atsushi Takabayashi, Junko Kishimoto, Tomomichi Fujita, Masakazu Iwai, Akio Murakami, Seiji Akimoto, Ayumi Tanaka
    第59回日本植物生理学会年会, Mar. 2018, English, 札幌コンベンションセンター, Domestic conference
    Public symposium

  • Photoprotection mechanisms of the drought-tolerant Jatropha curcas plant
    Helena Sapeta, Makio Yokono, Atsushi Takabayashi, Yoshifumi Ueno, Seiji Akimoto, Junko Kishimoto, Ayumi Tanaka, M. Margarida Oliveira, ○Ryouichi Tanaka
    第59回日本植物生理学会年会, Mar. 2018, English, 札幌コンベンションセンター, Domestic conference
    Poster presentation

  • 適応進化実験によるシアノバクテリア強光耐性株の獲得とその解析
    吉川 勝徳, 小川 健一, 戸谷 吉博, AKIMOTO SEIJI, 松田 史生, 清水 浩
    第9回日本光合成学会年会, 2018, Japanese, 仙台, Domestic conference
    Poster presentation

  • 単細胞緑藻Chlorella variabilis における低CO2条件での光捕集機能調整
    植野 嘉文, 嶋川 銀河, 三宅 親弘, AKIMOTO SEIJI
    第9回日本光合成学会年会, 2018, Japanese, 仙台, Domestic conference
    Poster presentation

  • 絶対蛍光強度測定による緑藻Chlorella variabilis におけるCO2条件に依存した光捕集機能調節の解明
    植野 嘉文, 嶋川 銀河, 藍川 晋平, 三宅 親弘, AKIMOTO SEIJI
    光合成セミナー2018：反応中心と色素系の多様性, 2018, Japanese, 神戸, Domestic conference
    Poster presentation

  • 珪藻におけるエネルギー移動過程の培養光質への応答
    AKIMOTO SEIJI, 植野 嘉文, 今西 悠貴, 岡 久美子, 沈 建仁, 長尾 遼
    光合成セミナー2018：反応中心と色素系の多様性, 2018, Japanese, 神戸, Domestic conference
    Oral presentation

  • 異なる光質に対する単細胞緑藻の光捕集機能調節
    植野 嘉文, 藍川 晋平, KONDO AKIHIKO, 秋本 誠志
    第59回日本植物生理学会年会, 2018, Japanese, Domestic conference
    Poster presentation

  • ヒメツリガネゴケの光化学系I–II超複合体の解析
    高林 厚史, 古川 亮, 田中 亮一, 田中 歩, 藤田 知道, AKIMOTO SEIJI, 横野 牧生
    第9回日本光合成学会年会, 2018, Japanese, 仙台, Domestic conference
    Poster presentation

  • ジアジノキサンチンサイクルを構成するカロテノイドの励起緩和ダイナミクス
    加賀谷 航平, 長尾 遼, 沈 建仁, 山野 由美子, 高市 真一, AKIMOTO SEIJI
    光合成セミナー2018：反応中心と色素系の多様性, 2018, Japanese, 神戸, Domestic conference
    Poster presentation

  • クロロフィル dを主要色素とするシアノバクテリア光化学系IIにおける分光特性
    豊福 玲於奈, 秋本 誠志, 篠田 稔行, 鞆達也
    日本生物物理学会 第56回年会, 2018, Japanese, Domestic conference
    Poster presentation

  • Spin convrsion of the singlet-fission-bornmultiexciton in the amorphous aggregates
    Hiroki Nagashima, Shuhei Kawaoka, Seiji Akimoto, Takashi Tachikawa, Yasunori Matsui, Hiroshi Ikeda, Yasuhiro Kobori
    The third joint conference of the Asia-Pacific EPR/ESR Society and the International EPR (ESR) Society (IES), 2018, English, Brisbane, International conference
    Oral presentation

  • Specreoscopic assignments of photosystem II complex in a chlorophyll d-dominated cyanobacterium
    豊福 玲於奈, 秋本 誠志, 篠田 稔行, 鞆達也
    International symposium on photosynthesis and chloroplast biogenesis, 2018, English, Kurashiki, International conference
    Poster presentation

  • Photoprotection mechanism of LHCSR in a green alga Chlamydomonas reinhardtii
    ○E. Kim, R. Tokutsu, K. Kosuge, Y. Ueno, M. Yokono, S. Akimoto, J. Minagawa
    1st Asia-Oceania International Congress on Photosynthesis, 2018, English, 北京, International conference
    Poster presentation

  • Multiple roles of light-harvesting-like proteins in the regulation and maintenance of the photosynthetic machinery
    K. Takahashi, Y. Kato, M. Yokono, AKIMOTO SEIJI, F. Myouga, K. Shinozaki, S. Ozawa, Y. Takahashi, A. Tanaka, A. Takabayashi, ○R. Tanaka
    Japan-Finland Seminar 2018, 2018, English, Kobe, International conference
    Poster presentation

  • Multiexciton dynamics in amorphous aggregates of singlet fission materials studied by time-Resolved EPR spectroscopy
    Hiroki Nagashima, Shuhei Kawaoka, Seiji Akimoto, Takashi Tachikawa, Yasunori Matsui, Hiroshi Ikeda, Yasuhiro Kobori
    10th Asian Photochemistry Conference (APC 2018), 2018, English, 台北, International conference
    Poster presentation

  • Modification of excitation energy-transfer processes of the glaucophyte Phaeodactylum tricornutum, in response to different light qualities
    植野 嘉文, AKIMOTO SEIJI
    International symposium on photosynthesis and chloroplast biogenesis, 2018, English, Kurashiki, International conference
    Poster presentation

  • Light adaptation of the pennate diatom Phaeodactylum tricornutum, probed by time-resolved fluorescence spectroscopy
    岡 久美子, 植野 嘉文, 長尾 遼, 沈 建仁, AKIMOTO SEIJI
    International symposium on photosynthesis and chloroplast biogenesis, 2018, English, Kurashiki, International conference
    Poster presentation

  • Differences in excitation relaxation dynamics of carotenoids with characteristic chemica structures
    加賀谷 航平, 山野 由美子, 長尾 遼, 沈 建仁, 高市 真一, AKIMOTO SEIJI
    International symposium on photosynthesis and chloroplast biogenesis, 2018, English, Kurashiki, International conference
    Poster presentation

  • Cryo-EM structures of PSII-FCPII complexes in the diatom Chaetoceros gracilis
    長尾 遼, 秋田 総理, 加藤 公児, 鈴木 健裕, 伊福 健太郎, 内山 郁夫, 菓子野 康浩, 堂前 直, AKIMOTO SEIJI, 宮崎 直幸, 沈 建仁
    1st Asia-Oceania International Congress on Photosynthesis, 2018, English, 北京, International conference
    Poster presentation

  • Cryo-EM structures of diatom PSII-FCPII supercomplexes
    長尾 遼, 秋田 総理, 加藤 公児, 鈴木 健裕, 伊福 健太郎, 内山 郁夫, 菓子野 康浩, 堂前 直, AKIMOTO SEIJI, 宮崎 直幸, 沈 建仁
    International symposium on photosynthesis and chloroplast biogenesis, 2018, English, Kurashiki, International conference
    Poster presentation

  • Chlorophyll f 蓄積過程における光化学系I複合体のエネルギー移動について
    篠田 稔行, 新井 啓史, 田伏 廣輝, 横野 牧生, AKIMOTO SEIJI, 鞆 達也
    光合成セミナー2018：反応中心と色素系の多様性, 2018, Japanese, 神戸, Domestic conference
    Oral presentation

  • Chlorophyll f 蓄積過程における光化学系I複合体のエネルギー移動とタンパク質組成の変化
    篠田 稔行, 新井 啓史, 田伏 廣輝, 横野 牧生, AKIMOTO SEIJI, 鞆 達也
    第20回日本光生物学協会年会, 2018, Japanese, 神戸, Domestic conference
    Oral presentation

  • Changes in excitation energy-transfer processes in photosynthesis under different environments
    ○S. Akimoto, S. Aikawa, A. Kondo
    Trombay Symposium on Radiation and Photochemistry (TSRP-2018), 2018, English, International conference
    [Invited]
    Invited oral presentation

  • Algal photoprotection: Mechanism and signal transduction
    ○J. Minagawa, Y. Aohara, K. Fujimura-Kamada, T. Yamazaki, E. Kim, R. Tokutsu, K. Kosuge, S. Akimoto, M. Yokono, Y. Ueno
    1st Asia-Oceania International Congress on Photosynthesis, 2018, English, Kurashiki, International conference
    Keynote oral presentation

  • ペンタセン・テトラセン誘導体における一重項分裂により生成した五重項状態の観測
    長嶋 宏樹, 松岡 秀平, 稲谷 隆太郎, AKIMOTO SEIJI, 松井 康哲, TACHIKAWA TAKASHI, 羽曽部 卓, 池田 浩, KOBORI YASUHIRO
    第56回電子スピンサイエンス学会年会（SEST2017）, Nov. 2017, Japanese, 東京工業大学, Domestic conference
    Oral presentation

  • 沈降式シリカ粒子による微細藻固定化およびその光エネルギー捕集機能
    浜田 文哉, AIKAWA SHINPEI, KONDO AKIHIKO, AKIMOTO SEIJI
    化学工学会 第49回秋季大会, Sep. 2017, Japanese, 名古屋大学 東山キャンパス, Domestic conference
    Poster presentation

  • 種々の溶液中におけるジアジノキサンチンの励起緩和ダイナミクス
    加賀谷 航平, 山野 由美子, 高市 真一, AKIMOTO SEIJI
    第25回 「光合成セミナー2017：反応中心と色素系の多様性」, Jul. 2017, Japanese, 神戸大学百年記念会館, Domestic conference
    Poster presentation

  • 光化学系における新規クロロフィルの局在部位
    鞆 達也, 富福 玲於奈, 篠田 稔行, AKIMOTO SEIJI
    第25回 「光合成セミナー2017：反応中心と色素系の多様性」, Jul. 2017, Japanese, 神戸大学百年記念会館, Domestic conference
    Oral presentation

  • 異なる光質条件下における緑藻Chlorella variabilisの光捕集機能変化の解明
    植野 嘉文, AIKAWA SHINPEI, KONDO AKIHIKO, AKIMOTO SEIJI
    第25回 「光合成セミナー2017：反応中心と色素系の多様性」, Jul. 2017, Japanese, 神戸大学百年記念会館, Domestic conference
    Poster presentation

  • ジビニルクロロフィル型シアノバクテリアProchlorococcusの光環境応答
    浜田 文哉, MURAKAMI AKIO, AKIMOTO SEIJI
    第25回 「光合成セミナー2017：反応中心と色素系の多様性」, Jul. 2017, Japanese, 神戸大学百年記念会館, Domestic conference
    Oral presentation

  • シアノバクテリア Synechococcus sp. PCC7942の光環境応答
    藤本 かおり, AIKAWA SHINPEI, KONDO AKIHIKO, AKIMOTO SEIJI
    第25回 「光合成セミナー2017：反応中心と色素系の多様性」, Jul. 2017, Japanese, 神戸大学百年記念会館, Domestic conference
    Poster presentation

  • Thermochromatium tepidum および Rhodobacter sphaeroides 由来ＬＨ1-ＲＣキメラ複合体の特性解析
    木村 行宏, AKIMOTO SEIJI, 今西 三千絵, 岸 利華子, 橋本 佳奈子, 大野 隆, 永島 賢治, 大友 征宇
    第25回 「光合成セミナー2017：反応中心と色素系の多様性」, Jul. 2017, Japanese, 神戸大学百年記念会館, Domestic conference
    Oral presentation

  • Thermochromatium tepidumおよびRhodobacter sphaeroides由来LH1-RCキメラ複合体の特性解析
    Kimura Yukihiro, AKIMOTO SEIJI, 今西三千絵, 岸利華子, 橋本佳奈子, Ohno Takashi, 永島賢治, 大友征宇
    第25回光合成セミナー：反応中心と色素系の多様性, Jul. 2017, Japanese, 神戸, Domestic conference
    Oral presentation

  • Chlorophyll f をもつ光化学系複合体の性質
    篠田 稔行, 新井 啓史, 田伏 廣輝, AKIMOTO SEIJI, 鞆 達也
    第25回 「光合成セミナー2017：反応中心と色素系の多様性」, Jul. 2017, Japanese, 神戸大学百年記念会館, Domestic conference
    Poster presentation

  • 77Kでの遅延蛍光スペクトル測定による光化学系間エネルギー移動の検討
    AKIMOTO SEIJI, 鞆 達也, MURAKAMI AKIO, 田中 歩
    第25回 「光合成セミナー2017：反応中心と色素系の多様性」, Jul. 2017, Japanese, 神戸大学百年記念会館, Domestic conference
    Oral presentation

  • 緑色植物の PSI–PSII 超複合体
    横野 牧生, 高林 厚史, 岸本 純子, 藤田 知道, 岩井 優和, MURAKAMI AKIO, AKIMOTO SEIJI, 田中 歩
    第8回日本光合成学会, May 2017, Japanese, 龍谷大学瀬田キャンパス, Domestic conference
    Poster presentation

  • 緑藻Chlamydomonas reinhardtii におけるCO2 に対する光捕集機能変化
    植野 嘉文, 嶋川 銀河, MIYAKE CHIKAHIRO, AKIMOTO SEIJI
    第58回日本植物生理学会年会, Mar. 2017, Japanese, 鹿児島大学郡元キャンパス, Domestic conference
    Poster presentation

  • 新奇Chlを持つシアノバクテリアより単離精製したユニークな吸収帯を持った光化学系II標品の分光解析
    篠田 稔行, 二井 大輔, AKIMOTO SEIJI, 鞆 達也
    第58回日本植物生理学会年会, Mar. 2017, Japanese, 鹿児島大学郡元キャンパス, Domestic conference
    Oral presentation

  • 高CO2 条件から低CO2 条件への移行に伴うシアノバクテリアの光合成初期過程の変化
    藤本 かおり, 嶋川 銀河, MIYAKE CHIKAHIRO, AKIMOTO SEIJI
    第58回日本植物生理学会年会, Mar. 2017, Japanese, 鹿児島大学郡元キャンパス, Domestic conference
    Poster presentation

  • 光合成ステート遷移におけるリン酸化LHCII の分子機能
    得津 隆太郎, Eunchul Kim, AKIMOTO SEIJI, 鎌田 このみ, 大西 紀和, 皆川 純
    第58回日本植物生理学会年会, Mar. 2017, Japanese, 鹿児島大学郡元キャンパス, Domestic conference
    Poster presentation

  • 異なる二酸化炭素濃度下で培養されたシアノバクテリアにおける光エネルギー捕集過程
    池田 志保, AIKAWA SHINPEI, 嶋川 銀河, MIYAKE CHIKAHIRO, KONDO AKIHIKO, AKIMOTO SEIJI
    第58回日本植物生理学会年会, Mar. 2017, Japanese, 鹿児島大学郡元キャンパス, Domestic conference
    Poster presentation

  • 異なる光環境下におけるシアノバクテリアProchlorococcusmarinusの光補集機能の変化
    浜田 文哉, MURAKAMI AKIO, AKIMOTO SEIJI
    第58回日本植物生理学会年会, Mar. 2017, Japanese, 鹿児島大学郡元キャンパス, Domestic conference
    Oral presentation

  • シロイヌナズナにおけるELIPの機能解析
    秋山 雄希, 横野 牧生, AKIMOTO SEIJI, 田中 歩, 田中 亮一
    第58回日本植物生理学会年会, Mar. 2017, Japanese, 鹿児島大学郡元キャンパス, Domestic conference
    Oral presentation

  • LHCSR3 dissipates the excitation energy of light-harvesting complexes in photosystem II supercomplexes
    ○Eunchul Kim, Ryutaro Tokutsu, Makio Yokono, Seiji Akimoto, Jun Minagawa
    第58回日本植物生理学会年会, Mar. 2017, English, Domestic conference
    Poster presentation

  • 光化学系ステート遷移におけるリン酸化 LHCII の分子機能
    得津 隆太郎, Eunchul Kim, 秋本 誠志, 横野 牧生, 鎌田 このみ, 大西 紀和, 皆川 純
    第8回日本光合成学会, 2017, Japanese, Domestic conference
    Poster presentation

  • ストロマラメラに局在するLight-harvesting-likeタンパク質LIL8の機能解析
    加藤 由佳子, 横野 牧生, 秋本 誠志, 高林 厚史, 田中 歩, 田中 亮一
    日本植物学会第81回大会, 2017, Japanese, Domestic conference
    Poster presentation

  • シアノバクテリアAcaryochloris marina の光化学系II反応中心複合体の性質
    豊福 玲於奈, 遠藤 嘉一郎, 篠田 稔行, 秋本 誠志, 鞆 達也
    日本植物学会第81回大会, 2017, Japanese, Domestic conference
    Poster presentation

  • ジアジノキサンチンの励起緩和ダイナミクス
    加賀谷 航平, 山野 由美子, 高市 真一, 秋本 誠志
    若手フロンティア研究会2017, 2017, Japanese, Domestic conference
    Poster presentation

  • クロロフィルf を持つシアノバクテリアの光化学系 II におけるエネルギー移動とその局在部位について
    篠田 稔行, 二井 大輔, 秋本 誠志, 鞆 達也
    第8回日本光合成学会, 2017, Japanese, Domestic conference
    Poster presentation

  • Spectral characterization of Photosystem II reaction center in a chlorophyll d-dominated cyanobacterium
    ○R. Toyofuku, K. Endo, T. Shinoda, S. Akimoto, T. Tomo
    第55回日本生物物理学会年会, 2017, English, Domestic conference
    Poster presentation

  • Spectral characterization of photosystem II reaction center complex isolated from the chlorophyll d-dominated cyanobacterium
    ○R. Toyofuku, S. Akimoto, T. Shinoda, S.I. Allakhverdiev, T. Tomo
    Photosynthesis Research for Sustainability – 2017, 2017, English, International conference
    Poster presentation

  • Spectral characterization of new chlorophyll containing cyanobacterium in the accumulation process of chlorophyll f
    ○T. Shinoda, K. Arai, H. Tabushi, S. Akimoto, T. Tomo
    第55回日本生物物理学会年会, 2017, English, Domestic conference
    Poster presentation

  • New chlorophylls in the primary processed of photosynthesis
    ○T. Tomo, T. Shinoda, R. Toyofuku, S. Akimoto, S.I. Allakhverdiev
    Photosynthesis Research for Sustainability – 2017, 2017, English, International conference
    [Invited]
    Invited oral presentation

  • Localization and characterization of chlorophylls f in photosystem I and II complexes
    ○T. Shinoda, S. Akimoto, S.I. Allakhverdiev, T. Tomo
    Photosynthesis Research for Sustainability – 2017, 2017, English, International conference
    Poster presentation

  • LHCSR1 stimulates Photosystem I dependent energy quenching in Chlamydomonas reinhardtii
    ○K. Kosuge, R. Tokutsu, E. Kim, S. Akimoto, M. Yokono, Y. Ueno, T.B. Truong, K.K. Niyogi, J. Minagawa
    Photosynthesis Research for Sustainability – 2017, 2017, English, International conference
    Poster presentation

  • Changes in light-harvesting and energy-transfer processes in response to CO2 concentrations
    ○S. Akimoto, S. Ikeda, S. Aikawa, A. Kondo
    Photosynthesis Research for Sustainability – 2017, 2017, English, International conference
    [Invited]
    Invited oral presentation

  • Acaryochloris marina 光化学系 II 反応中心複合体の分光学的性質について
    豊福 玲於奈, 遠藤 嘉一郎, 篠田 稔行, 秋本 誠志, 鞆 達也
    第8回日本光合成学会, 2017, Japanese, Domestic conference
    Poster presentation

  • 異種複合体発現系を用いたuphill型光合成反応の分子機構解析
    橋本佳奈子, AKIMOTO SEIJI, 大友征宇, 永島賢治, Ohno Takashi, Kimura Yukihiro
    若手フロンティア研究会2016, Dec. 2016, Japanese, 神戸, Domestic conference
    Poster presentation

  • ヘテロ複合体発現系を用いたuphill型光合成反応機構の解析
    橋本佳奈子, Kimura Yukihiro, AKIMOTO SEIJI, 永島賢治, 大友征宇, Ohno Takashi
    日本農芸化学会関西支部第497回講演会, Dec. 2016, Japanese, 神戸, Domestic conference
    Oral presentation

  • CO2 濃度変化に伴うシアノバクテリアの励起エネルギー移動の変化
    藤本 かおり, 嶋川 銀河, 三宅 親弘, 秋本 誠志
    若手フロンティア研究会2016, Dec. 2016, Japanese, Domestic conference
    Poster presentation

  • 新奇クロロフィルを持つシアノバクテリアより光化学系 II 標品の単離精製とエネルギー移動機構の解析
    ○T. Shinoda, D. Nii, S. Akimoto, T. Tomo
    第54回日本生物物理学会, Nov. 2016, Japanese, Domestic conference
    Poster presentation

  • Spectroscopic characterization of site-directed mutants in light-harvesting 1 complex from Thermochromatium tepidum
    Hashimoto Kanako, Nagashima V.P. Kenji, Akimoto Seiji, Ohno Takashi, Wang Zheng-Yu, Kimura Yukihiro
    The 54nd Annual Meeting of the BSJ, Nov. 2016, English, Tsukuba, Domestic conference
    Poster presentation

  • 時間分解蛍光分光法による緑藻Chlamydomonas reinhardtiiの光環境応答に関する研究
    関戸 彩乃, AIKAWA SHINPEI, KONDO AKIHIKO, AKIMOTO SEIJI
    第10回分子科学討論会2016神戸, Sep. 2016, Japanese, 神戸ファッションマート, Domestic conference
    Poster presentation

  • 高濃度二酸化炭素条件下で培養したシアノバクテリアの光応答
    藤本 かおり, 嶋川 銀河, MIYAKE CHIKAHIRO, AKIMOTO SEIJI
    第10回分子科学討論会2016神戸, Sep. 2016, Japanese, 神戸ファッションマート, Domestic conference
    Poster presentation

  • 異なるCO2濃度下で培養されたシアノバクテリアSynechocystis sp. PCC 6803の光合成初期過程の変化
    池田 志保, AIKAWA SHINPEI, KONDO AKIHIKO, AKIMOTO SEIJI
    第10回分子科学討論会2016神戸, Sep. 2016, Japanese, 神戸ファッションマート, Domestic conference
    Poster presentation

  • ピコ秒時間分解蛍光分光法によるフィコビリソームから光化学系への励起エネルギー移動過程に関する研究
    植野 嘉文, AIKAWA SHINPEI, KONDO AKIHIKO, AKIMOTO SEIJI
    第10回分子科学討論会2016神戸, Sep. 2016, Japanese, 神戸ファッションマート, Domestic conference
    Poster presentation

  • Photosystem I - photosystem II megacomplex in the green lineage
    Yokono M, Takabayashi A, Kishimoto J, Fujita T, Iwai M, Murakami A, Akimoto S, Tanaka A
    Finnish – Japanese symposium 2016, Integration of photosynthesis with cellular metabolism: towards sustainable bioeconomy, Sep. 2016, English, Lapland Hotel Riekonlinna, Saariselkä, Finland, International conference
    [Invited]
    Nominated symposium

  • 絶対蛍光強度測定による緑藻Chlamydomonas reinhardtiiにおける光捕集機能変化の解明
    植野 嘉文, 嶋川 銀河, MIYAKE CHIKAHIRO, AKIMOTO SEIJI
    第24回 「光合成セミナー2016：反応中心と色素系の多様性」, Jul. 2016, Japanese, 龍谷大学深草キャンパス, Domestic conference
    Poster presentation

  • 高濃度CO2条件下における光合成初期過程 −時間分解蛍光分光法による観測−
    池田 志保, 藍川 晋平, 近藤 昭彦, 秋本 誠志
    第24回 「光合成セミナー2016：反応中心と色素系の多様性」, Jul. 2016, Japanese, Domestic conference
    Oral presentation

  • 77 Kにおける蛍光の絶対強度測定 −シアノバクテリアの光応答−
    藤本 かおり, 嶋川 銀河, MIYAKE CHIKAHIRO, AKIMOTO SEIJI
    第24回 「光合成セミナー2016：反応中心と色素系の多様性」, Jul. 2016, Japanese, 龍谷大学深草キャンパス, Domestic conference
    Poster presentation

  • Excitation energy transfer processes among photosystethic complexes in cyanobacterial cells
    ○Yoshifumi Ueno, Shimpei Aikawa, Akihiko Kondo, Seiji Akimoto
    7th International Conference Photosynthesis Research for Sustainability-2016, Jun. 2016, English, Pushchino, Russia, International conference
    Poster presentation

  • Changes in light-harvesting and energy-transfer processes under different growth conditions
    Seiji Akimoto
    7th International Conference Photosynthesis Research for Sustainability-2016, Jun. 2016, English, Pushchino, Russia, International conference
    Oral presentation

  • 異なる二酸化炭素濃度下で培養されたシアノバクテリアの光合成初期過程の変化
    池田 志保, 藍川 晋平, KONDO AKIHIKO, 秋本 誠志
    第57回日本植物生理学会年会, Mar. 2016, Japanese, 盛岡, Domestic conference
    Poster presentation

  • ケトカロテノイドを有する色素タンパク質複合体における超高速エネルギー移動
    Seiji Akimoto, Mamoru Mimuro, Akio Murakami
    第57回日本植物生理学会年会, Mar. 2016, Japanese, 盛岡, Domestic conference
    Poster presentation

  • Ultrafast excitation energy transfer pathways in divinyl chlorophyll a/b-containing cyanobacterium, Prochlorococcus marinus
    浜田 文哉, MURAKAMI AKIO, 秋本 誠志
    第57回日本植物生理学会年会, Mar. 2016, Japanese, 盛岡, Domestic conference
    Poster presentation

  • Spillover in intact megacomplexes composed of phycobilisome and both photosystems in cyanobacterial cells
    Y. Ueno, Shimpei Aikawa, Akihiko Kondo, Seiji Akimoto
    第57回日本植物生理学会年会, Mar. 2016, Japanese, 盛岡, Domestic conference
    Oral presentation

  • 緑藻の励起エネルギー移動過程に対する培養光質の影響
    関戸 彩乃, 藍川 晋平, KONDO AKIHIKO, 秋本 誠志
    若手フロンティア研究会2015, Dec. 2015, Japanese, 神戸, Domestic conference
    Poster presentation

  • 異なるCO2濃度下で培養されたシアノバクテリアにおける励起エネルギー移動過程の観測
    池田 志保, 藍川 晋平, KONDO AKIHIKO, 秋本 誠志
    若手フロンティア研究会2015, Dec. 2015, Japanese, 神戸, Domestic conference
    Poster presentation

  • ラン藻中における光化学超複合体内のエネルギー移動
    植野 嘉文, 藍川 晋平, KONDO AKIHIKO, 秋本 誠志
    若手フロンティア研究会2015, Dec. 2015, Japanese, 神戸, Domestic conference
    Poster presentation

  • 緑藻Chlamydomonas reinhardtii の励起エネルギー移動過程に対する培養光質の影響
    関戸 彩乃, 藍川 晋平, KONDO AKIHIKO, 秋本 誠志
    2015年光化学討論会, Sep. 2015, Japanese, 大阪, Domestic conference
    Poster presentation

  • 微細藻の光化学超複合体における励起エネルギー移動過程の in vivo 測定
    植野 嘉文, 藍川 晋平, KONDO AKIHIKO, 秋本 誠志
    2015年光化学討論会, Sep. 2015, Japanese, 大阪, Domestic conference
    Poster presentation

  • シアノバクテリアの励起エネルギー移動過程に窒素欠乏が与える影響の時間分解蛍光分光法による考察
    大西 亜弥, 藍川 晋平, KONDO AKIHIKO, 秋本 誠志
    2015年光化学討論会, Sep. 2015, Japanese, 大阪, Domestic conference
    Oral presentation

  • シアノバクテリアSynechocystis sp. PCC 6803 の光合成初期過程に対する二酸化炭素濃度の影響
    池田 志保, 藍川 晋平, KONDO AKIHIKO, 秋本 誠志
    2015年光化学討論会, Sep. 2015, Japanese, 大阪, Domestic conference
    Poster presentation

  • Excitation relaxation dynamics and energy transfer in pigment-protein complexes containing keto-carotenoids
    Seiji Akimoto, Mamoru Mimuro, Akio Murakami
    Photosynthesis Research for Sustainability – 2015, Sep. 2015, English, Crete, Greece, International conference
    [Invited]
    Invited oral presentation

  • 緑藻Chlamydomonas reinhardtii の長期光環境応答
    関戸 彩乃, 藍川 晋平, KONDO AKIHIKO, 秋本 誠志
    光合成セミナー2015：反応中心と色素系の多様性, Jul. 2015, Japanese, 京都, Domestic conference
    Poster presentation

  • 超高速時間分解蛍光分光法によるシアノバクテリアProchlorococcus における光捕集機能の解明
    浜田 文哉, MURAKAMI AKIO, 秋本 誠志
    光合成セミナー2015：反応中心と色素系の多様性, Jul. 2015, Japanese, 京都, Domestic conference
    Oral presentation

  • 窒素栄養塩欠乏条件への順応がシアノバクテリアの励起エネルギー移動過程に与える影響
    大西 亜弥, 藍川 晋平, KONDO AKIHIKO, 秋本 誠志
    光合成セミナー2015：反応中心と色素系の多様性, Jul. 2015, Japanese, 京都, Domestic conference
    Poster presentation

  • 異なるCO2濃度下で培養されたシアノバクテリアにおけるエネルギー移動過程の観測
    池田 志保, 藍川 晋平, KONDO AKIHIKO, 秋本 誠志
    光合成セミナー2015：反応中心と色素系の多様性, Jul. 2015, Japanese, 京都, Domestic conference
    Poster presentation

  • シアノバクテリア光化学超複合体における励起エネルギー移動過程の in vivo 観測
    植野 嘉文, 藍川 晋平, KONDO AKIHIKO, 秋本 誠志
    光合成セミナー2015：反応中心と色素系の多様性, Jul. 2015, Japanese, 京都, Domestic conference
    Oral presentation

  • Interspecies distribution of PSI-PSII megacomplex may relate to quenching ability of PSI
    横野 牧生, 高林 厚史, 田中 歩, MURAKAMI AKIO, 秋本 誠志
    Photosynthesis (GRS) Gordon Research Seminar “Beyond Steady-State Photosynthesis: Emerging Model Organisms and Technologies., Jun. 2015, English, Bentley University, International conference
    [Invited]
    Invited oral presentation

  • 明所高温条件で誘導されるステート２によるPSII障害回避機構の解析
    丸谷 曜子, YAMAUCHI YASUO, 東山 真理, AKIMOTO SEIJI, 井上 加奈子, IKEDA KENICHI, MIZUTANI MASAHARU, SUGIMOTO YUKIHIRO
    日本植物生理学会, Mar. 2015, Japanese, 東京農業大学, Domestic conference
    Oral presentation

  • Long-term light adaptation of the unicellular red alga Cyanidioschyzon merolae, probed by time-resolved fluorescence spectroscopy,
    Y. Ueno, S. Aikawa, Akihiko Kondo, S. Akimoto
    第56回日本植物生理学会年会, Mar. 2015, Japanese, 東京, Domestic conference
    Poster presentation

  • Excitation energy transfer in thylakoid membranes from the chlorophyll f -containing cyanobacterium
    秋本 誠志, 篠田 稔行, M. Chen, S. I. Allakhverdiev, 鞆 達也
    第56回日本植物生理学会年会, Mar. 2015, English, 東京, Domestic conference
    Oral presentation

  • Excitation energy transfer in thylakoid membranes from the chlorophyll f -containing cyanobacterium
    AKIMOTO SEIJI, 篠田 稔行, Min Chen, Suleyman I. Allakhverdiev, 鞆 達也
    第56回日本植物生理学会年会, Mar. 2015, Japanese, 東京, Domestic conference
    Oral presentation

  • Energy transfer changes in Anabaena variabilis filaments under nitrogen depletion,
    A. Onishi, Shimpei Aikawa, Akihiko Kondo, Seiji Akimoto
    第56回日本植物生理学会年会, Mar. 2015, Japanese, 東京, Domestic conference
    Poster presentation

  • Changes in light-harvesting and energy-transfer processes under different cultivation lights, probed by time-resolved fluorescence spectroscopy
    秋本 誠志, 植野 嘉文, 藍川 晋平, 近藤 昭彦
    12th Nordic Photosynthesis Congress, Oct. 2014, English, Uppsala, Sweden, International conference
    Poster presentation

  • 時間分解蛍光分光法を用いた光合成初期過程の観測
    秋本 誠志
    光合成セミナー2014：反応中心と色素系の多様性, Jul. 2014, Japanese, 名古屋, Domestic conference
    [Invited]
    Invited oral presentation

  • 時間分解蛍光分光法を用いたAnabaena variabilis の窒素欠乏条件下におけるエネルギー移動過程の観測
    大西 亜弥, 藍川 晋平, 近藤 昭彦, 秋本 誠志
    光合成セミナー2014：反応中心と色素系の多様性, Jul. 2014, Japanese, 名古屋, Domestic conference
    Poster presentation

  • 異なる色素組成をもつフィコビリソームにおける励起エネルギー移動過程
    高下 友基, 村上 明男, 秋本 誠志
    光合成セミナー2014：反応中心と色素系の多様性, Jul. 2014, Japanese, 名古屋, Domestic conference
    Poster presentation

  • 異なる光質下で培養された紅藻Cyanidioschyzon merolae のエネルギー移動過程
    植野 嘉文, 藍川 晋平, 近藤 昭彦, 秋本 誠志
    光合成セミナー2014：反応中心と色素系の多様性, Jul. 2014, Japanese, 名古屋, Domestic conference
    Poster presentation

  • Spectroscopic analysis of chlorophyll f containing cyanobacteria
    T. Shinoda, D. Nii, T. Tomo, S. Akimoto, M. Chen, H. Ohta, S.I. Allakhverdiev
    Photosynthesis Research for Sustainability – 2014, Jun. 2014, English, Pushchino, Russia, International conference
    Poster presentation

  • Light adaptation of the primitive red alga Cyanidioschyzon merolae, proved by time-resolved fluorescence spectroscopy
    Y. Ueno, S. Aikawa, A. Kondo, S. Akimoto
    Photosynthesis Research for Sustainability – 2014, Jun. 2014, English, Pushchino, Russia, International conference
    Poster presentation

  • Energy transfer in Anabaena variabilis filaments during heterocyst differentiation studied by time-resolved fluorescence
    A. Onishi, S. Aikawa, A. Kondo, S. Akimoto
    Photosynthesis Research for Sustainability – 2014, Jun. 2014, English, Pushchino, Russia, International conference
    Poster presentation

  • Diversity of chlorophylls in photosynthesis
    T. Tomo, S. Akimoto, S.I. Allakhverdiev
    Photosynthesis Research for Sustainability – 2014, Jun. 2014, English, Pushchino, Russia, International conference
    [Invited]
    Invited oral presentation

  • Differences in energy transfer of cyanobacteria grown in different cultivation media
    S. Akimoto, K. Niki, S. Aikawa, A. Kondo
    Photosynthesis Research for Sustainability – 2014, Jun. 2014, English, Pushchino, Russia, International conference
    [Invited]
    Invited oral presentation

  • 新規クロロフィルを持つシアノバクテリアより光化学系 I 標品単離の試み
    篠田 稔行, 秋本 誠志, 二井 大輔, 太田 尚孝, 鞆 達也
    第5回日本光合成学会年会, May 2014, Japanese, 奈良, Domestic conference
    Poster presentation

  • 光合成系における励起エネルギー移動の環境応答
    秋本 誠志
    理研シンポジウム「最先端光計測とライフサイエンスの近未来 –バイオ・ラマン2017– [4]」, May 2014, Japanese, 仙台, Domestic conference
    [Invited]
    Invited oral presentation

  • コムギの光化学系における高温耐性機構の解析：ステート遷移の誘導と超高速励起型PSI-LHCII複合体の形成
    丸谷 曜子, YAMAUCHI YASUO, AKIMOTO SEIJI, 井上 加奈子, IKEDA KENICHI, MIZUTANI MASAHARU, SUGIMOTO YUKIHIRO
    第5回日本光合成学会年会, May 2014, Japanese, 近畿大学, Domestic conference
    Poster presentation

  • クロロフィルの光エネルギー捕集にみられる多様性
    秋本 誠志
    公開シンポジウム「多様な光合成の世界」、第5回日本光合成学会年会, May 2014, Japanese, 奈良, Domestic conference
    [Invited]
    Invited oral presentation

  • 始原的シアノバクテリア Gloeobacter violaceus PCC 7421 は人工的に獲得させたクロロフィルb に寛容である
    荒木 美英, 秋本 誠志, 三室 守, 土屋 徹
    第55回日本植物生理学会年会, Mar. 2014, Japanese, 富山, Domestic conference
    Poster presentation

  • 高温ストレスを受けたコムギにおけるチラコイド膜の構造変化を伴う光化学系の再編成：熱放散とステート遷移の誘導
    丸谷 曜子, YAMAUCHI YASUO, AKIMOTO SEIJI, 井上 加奈子, IKEDA KENICHI, MIZUTANI MASAHARU, SUGIMOTO YUKIHIRO
    第55回日本植物生理学会年会, Mar. 2014, Japanese, 富山大学, Domestic conference
    Poster presentation

  • クロロフィル f を持つシアノバクテリアの エネルギー移動機構の解析
    篠田 稔行, 秋本 誠志, M. Chen, S.I. Allakverdiev, 鞆 達也
    第55回日本植物生理学会年会, Mar. 2014, Japanese, 富山, Domestic conference
    Oral presentation

  • Excitation energy transfer in Synechococcus sp. PCC 7002 cells grown in brackish medium and seawater medium, probed by time-resolved fluorescence spectroscopy
    K. Niki, S. Aikawa, A. Kondo, S. Akimoto
    第55回日本植物生理学会年会, Mar. 2014, English, 富山, Domestic conference
    Poster presentation

  • Analysis of the of high-light stress tolerant strain of Synechocystis sp. PCC 6803
    K. Yoshikawa, K. Ogawa, S. Akimoto, Hiroshi Shimizu
    第55回日本植物生理学会年会, Mar. 2014, Japanese, 富山, Domestic conference
    Poster presentation

  • ”赤い”ラン藻における励起エネルギー移動過程
    高下 友基, 村上 明男, 秋本 誠志
    若手フロンティア2013, Dec. 2013, Japanese, 神戸, Domestic conference
    Oral presentation

  • Modification of energy-transfer processes in cyanobacteria to adapt light conditions, probed by time-resolved fluorescence spectroscopy
    S. Akimoto, M. Yokono, S. Aikawa, A. Kondo
    6th Asia & Oceania Conference on Photobiology (AOCP), Nov. 2013, English, Sydney, Australia, International conference
    Poster presentation

  • フィコエリスリンを有するラン藻における励起エネルギー移動
    高下 友基, 村上 明男, 秋本 誠志
    第51回 日本生物物理学会, Oct. 2013, Japanese, 京都, Domestic conference
    Poster presentation

  • Adaptation of light-harvesting systems of cyanobacteria to light conditions
    Seiji Akimoto
    1st Korea-Japan Microalgae Symposium, Oct. 2013, English, Daejeon, Korea, International conference
    [Invited]
    Invited oral presentation

  • 栄養欠乏ストレス条件下でのシアノバクテリアSynechococcus sp. PCC7002の励起エネルギー移動過程の観測
    仁木 健太, 横野 牧生, 藍川 晋平, 近藤 昭彦, 秋本 誠志
    第7回分子科学討論会, Sep. 2013, Japanese, 京都, Domestic conference
    Poster presentation

  • クロロフィルd を持つ藍藻Acaryochloris marinaにおける光捕集機能の解明
    山本 亜美, 横野 牧生, 鞆 達也, 土屋 徹, 秋本 誠志
    第7回分子科学討論会, Sep. 2013, Japanese, 京都, Domestic conference
    Oral presentation

  • Differences in excitation energy transfer of Arthrospira platensis cells grown in seawater medium and freshwater medium, probed by time-resolved fluorescence spectroscopy
    M. Arba, S. Aikawa, K. Niki, M. Yokono, A. Kondo, S. Akimoto
    第7回分子科学討論会, Sep. 2013, English, 京都, Domestic conference
    Poster presentation

  • 時間分解分光法による藍藻Acaryochloris marinaにおける光捕集機能の解明
    山本 亜美, 横野 牧生, 鞆 達也, 土屋 徹, 秋本 誠志
    第21回 光合成セミナー（光合成の色素系と反応中心に関するセミナー）, Jul. 2013, Japanese, 名古屋, Domestic conference
    Poster presentation

  • 時間分解蛍光分光法によるシアノバクテリアSynechococcus sp. PCC7002の栄養欠乏ストレスに対する適応の検討
    仁木 健太, 横野 牧生, 藍川 晋平, 近藤 昭彦, 秋本 誠志
    第21回 光合成セミナー（光合成の色素系と反応中心に関するセミナー）, Jul. 2013, Japanese, 名古屋, Domestic conference
    Oral presentation

  • シアノバクテリアの光環境応答
    秋本 誠志, 横野 牧生, 藍川 晋平, 近藤 昭彦
    第21回 光合成セミナー（光合成の色素系と反応中心に関するセミナー）, Jul. 2013, Japanese, 名古屋, Domestic conference
    Oral presentation

  • Excitation relaxation dynamics and energy transfer in fucoxanthin-chlorophyll a/c-protein
    S. Akimoto, A. Teshigahara, M. Yokono, R. Nagao, T. Tomo
    Photosynthesis Research for Sustainability, Jun. 2013, English, Baku, Azerbaijan, International conference
    [Invited]
    Invited oral presentation

  • 種々の光環境下で生育した藍藻 Arthrospira platensis におけるエネルギー移動過程 –時間分解蛍光分光法による解明
    Akimoto Seiji, YOKONO MAKIO, 濵田 文哉, 勅使河原, 彩香, 藍川 晋平, 近藤 昭彦
    第53回日本植物生理学会年会, Mar. 2012, Japanese, 日本植物生理学会, 京都, Domestic conference
    Poster presentation

  • 高温ストレスを受けた植物がステート遷移により PSII を保護するメカニズムの解析
    丸谷 曜子, 山内 靖雄, Akimoto Seiji, 木村 行宏, 水谷 正治, 杉本 幸裕
    第53回日本植物生理学会年会, Mar. 2012, Japanese, 日本植物生理学会, 京都, Domestic conference
    Poster presentation

  • BN-PAGEにより精製された光合成反応中心の時間分解蛍光スペクトルの測定
    YOKONO MAKIO, 高林 厚史, 栗原 克宜, 田中 歩, Akimoto Seiji
    第53回日本植物生理学会年会, Mar. 2012, Japanese, 日本植物生理学会, 京都, Domestic conference
    Poster presentation

  • 高温ストレスを受けた植物がステート遷移によりPSIIを保護するメカニズムの解析
    Marutani Yoko, Yamauchi Yasuo, Akimoto Seiji, Kimura Yukihiro, Mizutani Masaharu, Sugimoto Yukihiro
    第53回日本植物生理学会年会, 2012, Japanese, Domestic conference
    Oral presentation

  • Light adaptation of cyanobacteria probed by time-resolved fluorescence: Modification of energy transfer
    Akimoto Seiji, YOKONO MAKIO, F. Hamada, A. Teshigahara, S. Aikawa, A. Kondo
    Trombay Symposium on Radiation and Photochemistry (, Jan. 2012, English, Radiation & Photochemistry Division, Indian Society for Radiation & Photochemical Sciences, Mumbai, India, International conference
    [Invited]
    Invited oral presentation

  • 蛍光分光法によるシアノバクテリアの強光応答の波長依存性
    神戸 えりな, YOKONO MAKIO, 藍川 晋平, 近藤 昭彦, Akimoto Seiji
    若手フロンティア2011, Dec. 2011, Japanese, 神戸大学, 神戸, Domestic conference
    Poster presentation

  • 珪藻のアンテナ色素タンパク質におけるエネルギー移動過程の観測
    勅使河原, 彩香, YOKONO MAKIO, 長尾 遼, 鞆 達也, Akimoto Seiji
    若手フロンティア2011, Dec. 2011, Japanese, 神戸大学, 神戸, Domestic conference
    Poster presentation

  • 種々のホヤ中における藍藻Prochloronの励起緩和ダイナミクス
    濵田 文哉, YOKONO Makio, 広瀬 裕一, MURAKAMI Akio, AKIMOTO Seiji
    第5回分子科学討論会, Sep. 2011, Japanese, 分子科学会, 札幌, Domestic conference
    Poster presentation

  • ピコ秒時間分解蛍光分光法によるシアノバクテリアの強光応答に関する研究
    神戸 えりな, YOKONO MAKIO, 藍川 晋平, 近藤 昭彦, Akimoto Seiji
    第5回分子科学討論会, Sep. 2011, Japanese, 分子科学会, 札幌, Domestic conference
    Poster presentation

  • Fucoxanthin-Chlorophyll a/c-Proteinにおける超高速エネルギー移動過程
    勅使河原, 彩香, YOKONO MAKIO, 長尾 遼, 鞆 達也, Akimoto Seiji
    第5回分子科学討論会, Sep. 2011, Japanese, 分子科学会, 札幌, Domestic conference
    Poster presentation

  • シアノバクテリアSynechocystis sp. PCC 6803の強光応答
    神戸 えりな, YOKONO MAKIO, 藍川 晋平, 近藤 昭彦, Akimoto Seiji
    光合成の色素系と反応中心に関するセミナーXIX, Jul. 2011, Japanese, 大阪大学, 大阪, Domestic conference
    Poster presentation

  • シアノバクテリアProchloron における励起エネルギー移動
    濵田 文哉, YOKONO MAKIO, 広瀬 裕一, 村上 明男, Akimoto Seiji
    光合成の色素系と反応中心に関するセミナーXIX, Jul. 2011, Japanese, 大阪大学, 大阪, Domestic conference
    Poster presentation

  • シアノバクテリアProchlorococcusにおけるジビニルクロロフィルの励起緩和ダイナミクス
    Akimoto Seiji, YOKONO MAKIO, 村上 明男, 鞆 達也, 土屋 徹, 渡部 和幸, 三室 守
    光合成の色素系と反応中心に関するセミナーXIX, Jul. 2011, Japanese, 大阪大学, 大阪, Domestic conference
    Oral presentation

  • Prochlorococcusに保存されているPSII D1サブユニットのアミノ酸変異は励起エネルギーをCP47へ迂回させる
    YOKONO MAKIO, 鞆 達也, 長尾 遼, 伊藤 寿, 田中 歩, Akimoto Seiji
    光合成の色素系と反応中心に関するセミナーXIX, Jul. 2011, Japanese, 大阪大学, 大阪, Domestic conference
    Oral presentation

  • Optimization of light harvesting probed by time-resolved spectroscopy
    Akimoto Seiji, Yokono Makio, F. Hamada, A. Teshigahara, S. Aikawa, A. Kondo
    Photosynthesis Research for Sustainability, Jul. 2011, English, Suleyman I. Allakhverdiev, Baku, Azerbaijan, International conference
    [Invited]
    Invited oral presentation

  • Fucoxanthin-Chlorophyll a/c-Proteinにおけるクロロフィル間エネルギー移動
    勅使河原, 彩香, YOKONO MAKIO, 長尾 遼, 鞆 達也, Akimoto Seiji
    光合成の色素系と反応中心に関するセミナーXIX, Jul. 2011, Japanese, 大阪大学, 大阪, Domestic conference
    Poster presentation

  • Direct measurement of energy transfer in the Fucoxanthin-Chlorophyll a/c-Protein investigated by ultrafast spectroscopy
    勅使河原, 彩香, Yokono Makio, R. Nagao, T. Tomo, Akimoto Seiji
    5th Asia and Oceania Conference for Photobiology, Jul. 2011, English, 日本光生物学協会, Nara, Japan, International conference
    Poster presentation

  • Amino acid modifications improved excitation energy distribution in pigment-altered photosystem II reaction center
    Yokono Makio, T. Tomo, R. Nagao, H. Ito, A. Tanaka, Akimoto Seiji
    5th Asia and Oceania Conference for Photobiology, Jul. 2011, English, 日本光生物学協会, Nara, Japan, International conference
    Poster presentation

  • Comparison of Frequency Fluctuation between the Vibrational State and Electronic State in Aqueous Solution
    TOMINAGA Keisuke, J. Tayama, A. Kariya, M. Takatsuka, A. Ishihara, M. Banno, K. Ohta, S. Saito, S. Akimoto
    15th International Conference on Time-Resolved Vibrational Spectroscopy (TRVS), Jun. 2011, English, Ascona, Switzerland, International conference
    [Invited]
    Invited oral presentation

  • 遅延蛍光観測による紅藻の光合成系におけるスピルオーバーの解析
    YOKONO MAKIO, 村上 明男, Akimoto Seiji
    第52回日本植物生理学会年会, Mar. 2011, Japanese, 植物生理学会, 仙台, Domestic conference
    Poster presentation

  • 時間分解蛍光分光法による藍藻Arthrospira platensis の光環境適応の観測
    Akimoto Seiji, YOKONO MAKIO, 濵田 文哉, 勅使河原, 彩香, 藍川 晋平, 近藤 昭彦
    第52回日本植物生理学会年会, Mar. 2011, Japanese, 植物生理学会, 仙台, Domestic conference
    Oral presentation

  • 植物が光化学系の高温障害を回避するメカニズムの解析
    Marutani Yoko, Yamauchi Yasuo, Akimoto Seiji, Kimura Yukihiro, Mizutani Masaharu, Sugimoto Yukihiro
    日本農芸化学会関西・中部支部合同大会, 2011, Japanese, Domestic conference
    Oral presentation

  • ホヤに共生する藍藻Prochloron sp.における励起緩和ダイナミクス
    濵田 文哉, YOKONO Makio, 広瀬 裕一, MURAKAMI Akio, AKIMOTO Seiji
    若手フロンティア研究会2010, Dec. 2010, Japanese, 神戸大学, 神戸, Domestic conference
    Poster presentation

  • ケトカロテノイドの光捕集と励起緩和ダイナミクス
    Akimoto Seiji
    シンポジウム「光合成による光エネルギー利用の過去・現状・未来」, Dec. 2010, Japanese, 京都大学, 京都, Domestic conference
    [Invited]
    Invited oral presentation

  • Cyanobacterial symbiosis and photosynthetic performance in coral reef ascidians
    A. Murakami, H. Uchida, F. Hamada, Akimoto Seiji, E. Hirose
    Memorial Symposium for the 26th International Prize for Biology, Dec. 2010, English, 筑波大学, Tsukuba, Japan, International conference
    Poster presentation

  • Comparison of frequency fluctuation between the vibrational state and electronic state in aqueous solution
    TOMINAGA Keisuke, J. Tayama, A. Kariya, A. Ishihara, M. Banno, K. Ohta, S. Saito, S. Akimoto
    Molecular Dynamics in Complex Environments: Theory and Experiments, the International Chemical Congress of Pacific Basin Societies, Dec. 2010, English, Honolulu, USA, International conference
    [Invited]
    Invited oral presentation

  • Excitation relaxation dynamics of cyanobacteria, Spirulina spp. and Synechococcus spp.
    Akimoto Seiji, Yokono Makio, M. Tada, F. Hamada, T. Yamagishi, H. Kawai
    6th Asian Photochemistry Conference, Nov. 2010, English, Asian and Oceanic Photochemical Association, Wellington, International conference
    Poster presentation

  • Excitation relaxation dynamics of a chlorophyll b-containing cyanobacterium, Prochloron
    F. Hamada, Yokono Makio, E. Hirose, A. Murakami, Akimoto Seiji
    6th Asian Photochemistry Conference, Nov. 2010, English, Asian and Oceanic Photochemical Association, Wellington, International conference
    Poster presentation

  • Excitation energy transfer in chlorophyll-protein complexes of the unusual cyanobacterium, Prochloron
    F. Hamada, Yokono Makio, E. Hirose, A. Murakami, Akimoto Seiji
    Kobe University Molecular Photoscience Research Center International Symposium "New Horizons of Cluster Chemistry, Oct. 2010, English, 神戸大学, Kobe, Japan, International conference
    Poster presentation

  • 藍藻アカリオクロリス淡路株における励起エネルギー移動の励起波長依存性
    多田 愛, MURAKAMI Akio, YOKONO Makio, 福谷 通孝, TOMINAGA Keisuke, AKIMOTO Seiji
    第4回分子科学討論会, Sep. 2010, Japanese, 分子科学会, 大阪, Domestic conference
    Oral presentation

  • 種々の藍藻における励起緩和ダイナミクス –時間分解蛍光分光法による観測–
    Akimoto Seiji, YOKONO MAKIO, 多田 愛, 濵田 文哉, 山岸 隆博, 川井 浩史
    第48回日本生物物理学会, Sep. 2010, Japanese, 生物物理学会, 仙台, Domestic conference
    Poster presentation

  • 光合成系における遅延蛍光観測によるエネルギー移動経路の解析
    YOKONO Makio, 田中 一徳, 福谷 通孝, MURAKAMI Akio, AKIMOTO Seiji
    第4回分子科学討論会, Sep. 2010, Japanese, 分子科学会, 大阪, Domestic conference
    Poster presentation

  • ホヤに共生する藍藻Prochloron sp.における励起緩和ダイナミクス
    濵田 文哉, YOKONO Makio, 広瀬 裕一, MURAKAMI Akio, AKIMOTO Seiji
    第4回分子科学討論会, Sep. 2010, Japanese, 分子科学会, 大阪, Domestic conference
    Poster presentation

  • 水溶性ケトカロテノイドの励起緩和ダイナミクス
    岡田 祐一, 崔 錫宇, Akimoto Seiji
    光合成の色素系と反応中心に関するセミナーXVII, Jul. 2010, Japanese, 京都大学, 京都, Domestic conference
    Oral presentation

  • アンテナ系における色素の変換とその後の最適化
    三室 守, 村上 明男, 鞆 達也, 土屋 徹, 渡部 和幸, Akimoto Seiji
    光合成の色素系と反応中心に関するセミナーXVII, Jul. 2010, Japanese, 京都大学, 京都, Domestic conference
    Oral presentation

  • 渦鞭毛藻Symbiodinium sp.における光捕集とエネルギー伝達
    田中 一徳, 飯田 聡子, YOKONO MAKIO, 村上 明男, Akimoto Seiji
    第51回日本植物生理学会年会, Mar. 2010, Japanese, 日本植物生理学会, 熊本, Domestic conference
    Poster presentation

  • Generation of tunable light–source in the visible region and its application to observation of primary photosynthetic reactions
    Megumi Tada, Michitaka Fukuya, Akio Murakami, Keisuke Tominaga, Akimoto Seiji
    Asian Conference on Ultrafast Phenomena 2010, Jan. 2010, English, 国立台湾大学, Taipei, International conference
    Poster presentation

  • 光合成色素系におけるクロロフィルの励起緩和ダイナミクス
    Akimoto Seiji
    先端融合科学シンポジウム「ピロール系色素化合物の化学」, Dec. 2009, Japanese, 神戸大学, 神戸, Domestic conference
    [Invited]
    Invited oral presentation

  • 可視領域超短パルス光源の製作と生体観測への応用
    多田 愛, 福谷 通孝, 村上 明男, TOMINAGA KEISUKE, Akimoto Seiji
    先端融合科学シンポジウム「ピロール系色素化合物の化学」, Dec. 2009, Japanese, 神戸大学, 神戸, Domestic conference
    Poster presentation

  • 可視領域超短パルス光源の製作と光合成初期過程の観測への応用
    多田 愛, 福谷 通孝, 村上 明男, TOMINAGA KEISUKE, Akimoto Seiji
    若手フロンティア研究会２００９, Dec. 2009, Japanese, 神戸大学, 神戸, Domestic conference
    Poster presentation

  • 渦鞭毛藻Symbiodnium sp.の励起緩和ダイナミクス
    田中 一徳, YOKONO MAKIO, 飯田 聡子, 村上 明男, Akimoto Seiji
    先端融合科学シンポジウム「ピロール系色素化合物の化学」, Dec. 2009, Japanese, 神戸大学, 神戸, Domestic conference
    Poster presentation

  • フィコビリン系色素を持つ光合成アンテナの構造とエネルギー移動
    YOKONO MAKIO, Akimoto Seiji
    先端融合科学シンポジウム「ピロール系色素化合物の化学」, Dec. 2009, Japanese, 神戸大学, 神戸, Domestic conference
    Oral presentation

  • クロロフィルd を含む色素タンパク質複合体における励起エネルギー移動
    福谷 通孝, 内田 博子, YOKONO MAKIO, 村上 明男, TOMINAGA KEISUKE, Akimoto Seiji
    先端融合科学シンポジウム「ピロール系色素化合物の化学」, Dec. 2009, Japanese, 神戸大学, 神戸, Domestic conference
    Poster presentation

  • Excitation relaxation dynamics of a dinoflagellate Symbiodinium sp.
    Kazunori Tanaka, Makio Yokono, Satoko Iida, Akio Murakami, Akimoto Seiji
    The Second Asian Spectroscopy Conference, Nov. 2009, English, Seoul National University, Seoul, Korea, International conference
    Poster presentation

  • Excitation energy transfer in pigment-protein complexes containing chlorophyll d
    Michitaka Fukuya, Hiroko Uchida, Makio Yokono, Akio Murakami, Keisuke Tominaga, Seiji Akimoto
    The Second Asian Spectroscopy Conference, Nov. 2009, English, Seoul National University, Seoul, Korea, International conference
    Poster presentation

  • 時間分解蛍光分光法による渦鞭毛藻における励起エネルギー移動
    田中 一徳, 飯田 聡子, YOKONO Makio, MURAKAMI Akio, AKIMOTO Seiji
    2009年光化学討論会, Sep. 2009, Japanese, 光化学協会, 桐生, Domestic conference
    Oral presentation

  • クロロフィルd 型藻アカリオクロリス・淡路株の励起緩和ダイナミクス
    福谷 通孝, 村上 明男, 内田 博子, YOKONO MAKIO, TOMINAGA KEISUKE, Akimoto Seiji
    2009年光化学討論会, Sep. 2009, Japanese, 光化学協会, 桐生, Domestic conference
    Oral presentation

  • ジビニル型クロロフィルを持つシアノバクテリアにおける光化学系光阻害の機構
    鞆 達也, 岡崎 茂俊, 伊藤 寿, 日下部 勇人, Akimoto Seiji
    第15回日本光生物学協会年会, Aug. 2009, Japanese, 光生物学協会, 岡崎, Domestic conference
    Oral presentation

  • 淡水産紅藻の光捕集アンテナの塩濃度に対する応答
    YOKONO MAKIO, 村上 明男, Akimoto Seiji
    光合成の色素系と反応中心に関するセミナーXVII, Jul. 2009, Japanese, 京都大学, 京都, Domestic conference
    Oral presentation

  • 光合成細菌の色素タンパク質複合体におけるカロテノイドの励起緩和
    Akimoto Seiji
    光合成の色素系と反応中心に関するセミナーXVII, Jul. 2009, Japanese, 京都大学, 京都, Domestic conference
    Oral presentation

  • クロロフィル及びフェオフィチンをジビニル型に置換した光化学系IIの性質
    鞆 達也, Akimoto Seiji
    光合成の色素系と反応中心に関するセミナーXVII, Jul. 2009, Japanese, 京都大学, 京都, Domestic conference
    Oral presentation

  • Acaryochloris sp. strain Awajiのフィコビリンタンパク質におけるエネルギー移動
    福谷 通孝, YOKONO MAKIO, 村上 明男, Akimoto Seiji
    光合成の色素系と反応中心に関するセミナーXVII, Jul. 2009, Japanese, 京都大学, 京都, Domestic conference
    Poster presentation

  • クロロフィルd 型ラン藻Acaryochloris sp. strain Awajiにおける励起エネルギー移動
    福谷 通孝, 内田 博子, MURAKAMI Akio, AKIMOTO Seiji
    若手フロンティア研究会2008, Dec. 2008, Japanese, 神戸大学, 神戸, Domestic conference
    Poster presentation

  • 77 Kにおける渦鞭毛藻の超高速時間分解蛍光
    田中 一徳, 飯田 聡子, MURAKAMI Akio, AKIMOTO Seiji
    若手フロンティア研究会2008, Dec. 2008, Japanese, 神戸大学, 神戸, Domestic conference
    Poster presentation

  • 渦鞭毛藻Alexandrium tamarense における光エネルギー捕集とエネルギー移動
    田中 一徳, 飯田 聡子, Yokono Makio, 小檜山 篤志, 緒方 武比古, Murakami Akio, Akimoto Seiji
    2008年光化学討論会, Sep. 2008, Japanese, 光化学協会, 大阪, Domestic conference
    Poster presentation

  • 常緑樹イチイにおける励起エネルギー緩和の季節変化
    YOKONO MAKIO, Akimoto Seiji
    第16回光合成の色素系と反応中心に関するセミナー, Jun. 2008, Japanese, 京都大学, 京都, Domestic conference
    Oral presentation

  • 渦鞭毛藻Alexandrium tamarense の蛍光特性
    田中 一徳, 飯田 聡子, YOKONO MAKIO, 小檜山 篤志, 緒方 武比古, MURAKAMI AKIO, Akimoto Seiji
    第16回光合成の色素系と反応中心に関するセミナー, Jun. 2008, Japanese, 京都大学, 京都, Domestic conference
    Poster presentation

  • Acaryochloris sp. strain Awaji の光環境応答
    福谷 通孝, 内田 博子, YOKONO MAKIO, MURAKAMI AKIO, Akimoto Seiji
    第16回光合成の色素系と反応中心に関するセミナー, Jun. 2008, Japanese, 京都大学, 京都, Domestic conference
    Poster presentation

  • Acaryochloris marina の光化学系Iの性質について
    鞆 達也, 加藤 樹, 鈴木 健裕, Akimoto Seiji
    第16回光合成の色素系と反応中心に関するセミナー, Jun. 2008, Japanese, 京都大学, 京都, Domestic conference
    Oral presentation

  • Excitation relaxation of carotenoids probed by time-resolved fluorescence spectroscopy
    Akimoto Seiji, Mimuro Mamoru
    Trombay Symposium on Radiation and Photochemistry, Jan. 2008, English, Radiation & Photochemistry Division, Indian Society for Radiation & Photochemical Sciences, Pune, India, International conference
    [Invited]
    Invited oral presentation

  • Excited state dynamics and functions of carotenoids in the light-harvesting complexes II
    Akimoto Seiji, Yokono Makio, Tomo Tatsuya, Murakami Akio, Mimuro Mamoru
    7th International Conference on Tetrapyrrole Photoreceptors in Photosynthetic Organisms, Dec. 2007, English, 京都大学, Kyoto, Japan, International conference
    Poster presentation

  • Components and photochemical reactions in photosystem II of the Chl d -dominated cyanobacterium, Acaryochloris marina
    Mimuro Mamoru, Tomo Tatsuya, Tsuchiya Toru, T. Ohkubo, Noguchi Takumi, Akimoto Seiji
    7th International Conference on Tetrapyrrole Photoreceptors in Photosynthetic Organisms, Dec. 2007, English, 京都大学, Kyoto, Japan, International conference
    [Invited]
    Invited oral presentation

  • ケトカロテノイドの電子励起状態に関する考察
    Akimoto Seiji, Mimuro Mamoru
    第15回光合成の色素系と反応中心に関するセミナー, Jul. 2007, Japanese, 京都大学, 京都, Domestic conference
    Oral presentation

  • Unique optical properties of LHC II isolated from Codium fragile - its correlation to protein environment
    Tsuchiya Toru, Tomo Tatsuya, Akimoto Seiji, Murakami Akio, Mimuro Mamoru
    14th International Congress of Photosynthesis, Jul. 2007, English, International Society of Photosynthesis Research, Glasgow, U.K., International conference
    Poster presentation

  • Ultrafast relaxation dynamics of a keto-carotenoid, siphonaxanthin, probed by time-resolved fluorescence
    Akimoto Seiji, Yokono Makio, Higuchi Mitchiya, Murakami Akio, Takaichi Shinichi, Mimuro Mamoru
    14th International Congress of Photosynthesis, Jul. 2007, English, International Society of Photosynthesis Research, Glasgow, U.K., International conference
    Poster presentation

  • Identification of special pair and ChlZ of Photosystem II in Acaryochloris marina
    Tomo Tatsuya, Okubo T, Akimoto Seiji, Miyashita H, Tsuchiya Toru, Noguchi Takumi, Mimuro Mamoru
    14th International Congress of Photosynthesis, Jul. 2007, English, International Society of Photosynthesis Research, Glasgow, U.K., International conference
    Poster presentation

  • Excitation energy transfer within the PSI-LHCI/II supercomplex from Chlamydomonas reinhardtii in state 2
    Minagawa J, Yokono Makio, Iwai M, Akimoto Seiji
    14th International Congress of Photosynthesis, Jul. 2007, English, International Society of Photosynthesis Research, Glasgow, U.K., International conference
    Poster presentation

  • Excitation energy transfer in PS I of the cyanobacterium Gloeobacter violaceus PCC 7421 that lacks the long-wavelength form of chlorophyll a
    Mimuro Mamoru, Higuchi Mitchiya, Inoue H, Yokono Makio, Tsuchiya Toru, H. Miyashita, Akimoto Seiji
    14th International Congress of Photosynthesis, Jul. 2007, English, International Society of Photosynthesis Research, Glasgow, U.K., International conference
    Poster presentation

  • 溶液中におけるケトカロテノイドの超高速励起緩和
    Akimoto Seiji, Murai Yosuke, Yokono Makio, Murakami Akio, Takaichi Shinichi, Higuchi Mitchiya, Tomo Tatsuya, Mimuro Mamoru
    第23回化学反応討論会, Jun. 2007, Japanese, 神戸大学, 神戸, Domestic conference
    Poster presentation

  • 時間分解蛍光分光法によるカロテノイドの励起緩和ダイナミクスの観測
    Akimoto Seiji
    123回物理化学セミナー, Jun. 2007, Japanese, 神戸大学, 神戸, Domestic conference
    [Invited]
    Invited oral presentation

  • 光化学系II-CP43欠損株における蛍光特性
    嶋田 友一郎, Tsuchiya Toru, Akimoto Seiji, Tanaka Kazunori, Fukuya Mchitaka, Tomo Tatsuya, Mimuro Mamoru
    第49回日本植物生理学会年会, Mar. 2007, Japanese, 日本植物生理学会, 札幌, Domestic conference
    Poster presentation

  • クロロフィル d を主要色素としてもつシアノバクテリアの光化学系Iのサブユニット組成と光化学反応の解析
    Tomo Tatsuya, 加藤 祐樹, 鈴木 健裕, Akimoto Seiji, Noguchi Takumi, Tsuchiya Toru, 堂前 直, 渡辺 正, Mimuro Mamoru
    第49回日本植物生理学会年会, Mar. 2007, Japanese, 日本植物生理学会, 札幌, Domestic conference
    Poster presentation

  • クロロフィルdを主要色素としてもつシアノバクテリアの光化学系II複合体の単離精製
    鞆 達也, 大久保 辰則, 秋本 誠志, 横野 牧生, 土屋 徹, 野口 巧, 宮下 英明, 三室 守
    第48回日本植物生理学会年会, Mar. 2007, Japanese, 日本植物生理学会, 愛媛大学, Domestic conference
    Poster presentation

  • 溶液中におけるシフォナキサンチンの励起緩和過程
    村井 陽介, 横野 牧生, 秋本 誠志, 村上 明男, 高市 真一, 樋口 倫也, 三室 守
    日本化学会北海道支部2007年冬季研究発表会, Feb. 2007, Japanese, 日本化学会北海道支部, 北海道大学学術交流会館, Domestic conference
    Oral presentation

  • シクロデキストリン包接によるサイズ選択的なゲスト分子の吸収・蛍光スペクトル尖鋭化
    木場 隆之, 佐藤 信一郎, 笠嶋 辰也, 仁戸部 覚, 秋本 誠志, 覚知 豊次
    日本化学会北海道支部2007年冬季研究発表会, Feb. 2007, Japanese, 日本化学会北海道支部, Domestic conference
    Oral presentation

■ Research Themes
  • 人工培養系に適した実用藻類ツノケイソウの光合成システムの創出
    伊福 健太郎, 長尾 遼, 秋本 誠志
    日本学術振興会, 科学研究費助成事業, 基盤研究(B), 京都大学, 01 Apr. 2023 - 31 Mar. 2026

  • 常緑針葉樹の光合成調節機構の複合体プロテオミクスおよび分光学的手法よる統合的解析
    田中 亮一, 秋本 誠志, 北尾 光俊
    日本学術振興会, 科学研究費助成事業, 基盤研究(B), 北海道大学, 01 Apr. 2020 - 31 Mar. 2024
    森林総研北海道支所において、イチイ、トドマツ、エゾマツ、アカエゾマツ、ヒノキアスナロの苗を栽培し、それぞれ、Sun（直射日光が当たる条件）とShade（寒冷紗によって被陰舌条件）で生育した。また、北大・低温研においては、2 mから8 mのサイズのイチイを材料に以下の研究を実施した。年間を通して、光化学系IIの量子収率(YII)と最大量子収率(Fv/Fm)を測定し、季節・気温によって、YIIが減少するタイミングを調べた。また、光合成色素の変動を調べ、RNAとタンパク質の変動を調べるため、サンプリングを行った。この結果、春から秋にかけては、葉に当たる光強度とYIIは逆相関を示したが、冬においては、すでに報告されている通り、YIIは光強度の相関はほとんど示さず、常に低い値を示した。一方、冬季はYIIは気温に強い相関を示した。自然条件における、このような気温との強い相関の報告は初めてである。春から秋にかけては、クロロフィルとカロテノイドの比率はほぼ一定であったが、冬にはxanthophyll cycleの色素であるzeaxanthinがクロロフィルあたりで数倍に上昇した。この結果は、春から秋にかけては、光化学系タンパク質にこれらのクロロフィルとカロテノイドが結合していることを示しているが、冬には、xanthophyll cycleの色素は光化学系タンパク質には結合していないことを示唆している。また、chlorophyll a/b比がSun条件下で顕著に増加した。この結果から、冬季のSun条件下においてchlorophyllおよびzeaxanthinを結合するタンパク質の増加が強く示唆された。

  • Feedback regulation of Light-harvesting via proton gradient
    Minagawa Jun
    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area), National Institute for Basic Biology, 30 Jun. 2016 - 31 Mar. 2021
    The mechanism of thermal dissipation of excess energy of light has been unknown, but by purifying and examining the PSII-LHCII supercomplex from a green alga Chlamydomonas reinhardtii grown in high light, it was clarified that the LHCSR3 induces non-photochemical quenching and that LHCSR1 transfers excess energy to PSI. Furthermore, the gene expression analysis of the high light-inducible LHCSR3 and the UV-inducible LHCSR1 revealed their signal transduction pathways. We also developed a new purification method using amphipol, an amphiphilic polymer, and revealed the structure of the PSII-LHCII supercomplex for the first time.

  • Roles of Ca2+ in uphill energy transfer of purple photosynthetic bacteria
    KIMURA YUKIHIRO, Otomo Seiu, Akimoto Seiji
    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (C), Kobe University, 01 Apr. 2016 - 31 Mar. 2019
    Thermophilic purple sulfur bacteirum Thermochromatium tepidum exhibits its light-harvesting 1 (LH1) Qy absorption at 915 nm in the near-infrared region. The LH1 complex transfers the low light energy into a reaction center (RC) against the energy barrier (uphill energy transfer) to initiate the photosynthetic charge separation. Interestingly, Ca2+ is a possible factor to be involved in this uphill energy transfer to function as a binder of the RC and a redox-active C-subunit. The binding of the C-subunit to the RC results in the lowering of the Qy transition energy of the special pair to enable the uphill enrgy transfer smoothly.

  • Elucidating the fundamental questions "photochemical reaction and its site" using unique cyanobacteria
    TSUCHIYA Tohru, AKIMOTO Seiji, TOMO Tatsuya
    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (B), Kyoto University, 2010 - 2012
    We studied the photochemical reaction of photosystems that convert light energy into chemical energy and thylakoid membranes formation as fundamental questions. Photosystem II complexes isolated from a chlorophyll d-dominated cyanobacterium that can utilized near infra-red light for photochemical reaction unlike plantswere analyzed. The results revealed the bioenergetics of photosystems driven by lower energy than those from plants.

  • 村上 明男
    科学研究費補助金／基盤研究(B), 2011
    Competitive research funding

  • AKIMOTO S eiji
    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (B), Kobe University, 2007 - 2008, Principal investigator
    太陽光から得たエネルギーを電子の流れへと変換を行う光合成反応中心、および、その周りに存在する色素タンパク質では、巧みに色素分子が配列され、エネルギーの流れの制御がなされている。本研究では、反応中心が必要とするエネルギーより低いエネルギーを持つ色素に着目し、(1) 様々な光合成色素タンパク質に存在する低エネルギー色素の同定、(2) 低エネルギー色素の光合成における機能、(3) 低エネルギー色素の発現法、について考察した。
    Competitive research funding

  • Studies on unique light-harvesting systems in photosynthesis and their applications
    AKIMOTO Seiji
    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (C), HOKKAIDO UNIVERSITY, 2004 - 2005
    Ultrafast excitation relaxation dynamics and energy transfer processes in the light-harvesting complex II(LHC II) of Arabidopsis thaliana and those in chloroplasts of the siphonaxanthin(Siph)-containing green alga Codium fragile, were examined at physiological temperature using femtosecond time-resolved fluorescence spectroscopy. In the A.thaliana LHC II, energy transfer from lutein to Chl α proceeded with a rate constant of k_=1.8-1.9×10^<13>s^<-1> and a yield of approximately φ_=0.70, whereas that from neoxanthin to Chl α had a rate constant of k_=6.5×10^<11>s^<-1> and a yield at the most of φ_=0.09. Fluorescence anisotropy decay of lutein in LHC II showed a value larger than 0.4 at the initial state and decayed to approximately 0.1 in 0.3 ps, indicating that two lutein molecules interact with each other in LHC II. On the other hand, Siph in the C.fragile chloroplasts exhibited a new absorption band at approximately 530 nm. Based on fluorescence anisotropy decay and an anisotropy value of r(t)=0.30, the origin of this band was determined as a new excited state (S_X) located between the S_2 and S_1 states. The S_2 (or S_x) fluorescence lifetime of Siph was observed as being identical both in a benzene solution and in the chloroplasts, indicating that an efficient Siph-to-chlorophyll (Chl) α energy transfer is achieved only via the S_1 state of Siph. This was confirmed by fluorescence anisotropy decay measurements ; the Siph S_1 fluorescence lost its polarization with a time constant 400 fs, which corresponded to the energy transfer time from the S_1 state of Siph to the Chl α.

  • 生体および人工分子配列系における超高速コヒーレントエネルギー移動
    秋本 誠志
    日本学術振興会, 科学研究費助成事業, 若手研究(B), 北海道大学, 2002 - 2004
    生体および人工分子配列系に取り込まれた色素分子間の励起エネルギー移動過程を超高速蛍光分光法により追跡し、分子配列系に固有のコヒーレント光化学過程(光量子ダイナミクス)を観測するとともにその機構を明らかにすることを目標として、以下の研究を行った。 (1)種々のアントラセン2量体について蛍光異方性減衰曲線を測定し、励起子伝搬に伴う量子ビートを2つのアントラセン間の配向の関数として観測することに成功した。量子ビートの振動周期は2分子間の相互作用エネルギーに、電子位相緩和時間は2分子の相対的な配置に依存することを初めて実験的に示した。 (2)有機溶媒中におけるペリレンおよびその誘導体の蛍光減衰曲線を測定し、振動余剰エネルギーの緩和過程について検討した。振動モード内と振動モード間とでは熱平衡状態に至るまでの時間のずれがあることを明らかにした。 (3)緑藻ミルの光捕集アンテナ色素タンパク質におけるカロテノイド(シフォナキサンチン)からクロロフィルへの光励起エネルギー伝達過程について検討した。シフォナキサンチンの第一電子励起状態からの励起エネルギー移動を実時間で追跡することに成功した。エネルギー移動の時定数として400フェムト秒(移動効率ほぼ100%)が得られ、本来禁制帯である第一電子励起状態を介して高効率のエネルギー移動が実現されていることがわかった。また、シフォナキサンチンは緑藻ミル中で特異的な蛍光異方性を示すが、これは、シフォナキサンチンとタンパク質との間の相互作用によるもの考えられる

  • Photonic Molecular Processors by means of Quantum Phase Control of Electron and Exciton Transport
    YAMAZAKI Iwao, NISHIMURA Yoshinobu, AKIMOTO Seiji, SATO Shin-ichiro
    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (B), HOKKAIDO UNIVERSITY, 2002 - 2003
    In highly organized molecular systems, the coherent photochemical reactions such as excitation transfer and electron transfer can occur very fast (less than 1 ps) as a coherent motion of quantum mechanical wavepacket. The present work has been started with observation of the quantum coherence of exciton motion in molecular dimers of anthracene, perylene and in porphyrin dendrimers. Quantum beats appeared on fluorescence anisotropy decay which means the oscillatory motion of exciton in the course of energy transfer processes into the final state. The phase-locked double-pulse excitation method has been developed and provided us with another method to examine the quantum coherence of the reaction. Furthermore, this method allowed us to examine the photoswitching behavior of the coherent photoreaction by controlling the phase of two laser pulses.

  • フェムト秒蛍光分光法を用いた超高速電子移動・エネルギー移動に関する研究
    秋本 誠志
    日本学術振興会, 科学研究費助成事業, 奨励研究(A), 北海道大学, 2000 - 2001
    フェムト秒蛍光アップコンバージョン法を用いて、ポルフィリン環状多量体、ポルフィリンアレー、ポルフィリン風車型多量体のフェムト秒時間分解蛍光スペクトルの測定を行った。これらの分子配列系ではポルフィリン間の相互作用が強く、内部転換・振動緩和と競合しながら、100フェムト秒前後で励起エネルギー移動・励起の非局在化が起こることがわかった。ポルフィリン配列分子の光機能材料としての可能性を検討した。 種々のカロテノイドのフェムト秒時間分解蛍光スペクトルを、295Kおよび77Kにおいて測定した。カロテノイドに与えられた余剰エネルギーが緩和していく過程およびその時定数を明らかにした。炭化水素からなるカロテノイドでは振動再分配がクロロフィルへのエネルギー移動と競合するのに対して、ケトカルボニル基を有するカロテノイドでは振動再分配は30フェムト秒以内で起こることがわかった。カロテノイドの構造と光合成系における役割との関連を励起緩和ダイナミクスの観点から検討した。 シングルチョッパー法を発展させたデュアルチョッパーロックイン検出法を新たに開発し、プローブレーザー光に由来するノイズと励起レーザー光に由来するノイズとを同時に削除し、ノイズフリーの条件下での測定を可能とした。これまでS/N比を向上させるためには光学系の念入りな調整が必要であったが、この方法により、容易にノイズとシグナルを分離することが可能となった。これに伴い励起波長範囲が拡大され、多種多様なサンプルについての測定が可能となった。

  • Coherent Photochemical Reactions in Sequential Molecular Systems-Measurement and Theoretical Formulation
    YAMAZAKI Iwao, SATO Shin-ichiro, OHTA Nobuhiro, SUMI Hitoshi, AKIMOTO Seiji, NISHIMURA Yoshinobu
    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research on Priority Areas (B), HOKKAIDO UNIVERSITY, 1999 - 2001
    The Coherent nature of photochemical reaction has been established for highly organized molecular systems through the experimental mesurement and theoretical formulation. The results are summarized as follows. (1) The first observation of quantum beat signal has been attained for cyclic motion of exciton between two chromophores inanthracene dimers and perylene dimers. This means that the exciton moves coherently back and forth between the two chromophores, and that the photochemical reaction in molecular systems occurs coherently in several ps before the electronic decoherence. A special apparatus was constructed which was capable of quantum-interference control of the reaction. (2) The coherent photochemical reaction under external electric field was investigated, and found that the reaction was controlled by applying electric field. Several types of porphyrin arrays of 1D (Osuka compounds) exhibited a significant enhancement of conductivity upon photoexcitation. These molecular systems may function as molecular wires switchable by photo-irradiation. (3) The theoretical formulation has been established for coherent transports of electron and exciton in photosynthetic reaction centers (RC) in plants A higher-order perturbation theory was applied to the cyclic and sequential arrangements of molecules inside the RC proteins. In Summary, the present reserch project has attained 90% success for the reserch program that we planned initially.

  • Sequential photochemical processes in biological and artificial molecular systems
    YAMAZAKI Iwao, AKIMOTO Seiji, NISHIMURA Yoshinobu, OHTA Nobuhiro, MIMURO Mamoru, OSUKA Atsuhiro
    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (A), HOKKAIDO UNIVERSITY, 1997 - 1999
    This research project aims at presenting a new aspect of photochemical processes in highly organized molecular systems in which reacting molecules are located with close proximity and optimal orientation. The reaction dynamics of ultrafast and non-equilibrium processes in electron transfer and excitation transfer were monitored with femtosecond time-resolved fluorescence spectroscopy. The result of this study is summarized in the following. (1) In Langmuir-Blodgett multilayers, it was found that the inter- and intra-layer excitation transfer took place much faster at room temperature (ca. 10 ps) than in 10K (ca. 50 ps). The theoretical analyses suggest that the spatical fluctuation of molecules may play an important role in excitation transfer. (2) In artificial porphyrin arrays and photosynthetic carotenoid-chlorophyll systems, the excitation energy transfer occurs directrly from the donor S2 state during 80-140 fs before thermal equilibration. This finding violates the well-known Kasha's rule that the photochemical reaction proceeds from the thermally equilibrated lowest excited state. (3) External electric field effect It was found that the electron transfer in LB films undergoes the external electrid field and its reaction rate depend stronly on the initially excited state. The results of the project are now directed toward development of quantum computing elecments and photo-switching molecular devices.

  • An instrument for measuring ultrafast photophysical dynamics in photonic molecular devices
    YAMAZAKI Iwao, KOISHI Musubu, AKIMOTO Seiji, NISHIMURA Yoshinobu, OHTA Nobuhiro
    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (A), HOKKAIDO UNIVERSITY, 1997 - 1998
    Recent advance in developing photonic molecular devices to ultrafast photophysical dynamics. Researchers need experimental tools capable of probing the phenomena with time-resolution of order of 10 femtosecond. This research project is directed toward developing an instrument for femtosecond time-resolved measurement of fluorescence emitted from organic thin films like LB films and liquid crystal thin films. The system is based on the method of fluorescence up-conversion, particularly based on a lock-in-detection method which enables us with highly sensitive measurement of very weak fluorescence emission from organic thin films. During two years of this project, the work has been almost accomplished ; the system consist of (1) a femtosecond pulsed laser (Ti : Sapphire tunable laser), (2) a fluorescence up-conversion system with lock- in detection system, (3) a sample holder moving the analyzing the experimental data. The instrument has been produced which has specification of the time-resolution of 10 fs, the instrumental sensitivity 50-fold higher than ordinary fluorescence up-conversion instrument. This system of the lock-in detection method has been proven to be a powerful tool for studying photonic molecular devices.

  • 異積多層膜中における励起エネルギー緩和機構に関する研究
    秋本 誠志
    日本学術振興会, 科学研究費助成事業, 奨励研究(A), 北海道大学, 1995 - 1995
    本研究は以下の2点にまとめられる。 1.ストリークカメラを用いた高速蛍光分光法の開発 次項で問題となるような高速現象を捕らえるためには、既存の方法では不十分であり、新たにピコ秒からサブプコ秒の時間分解能をもった波長-時間の二次元測光法が必要となる。そこで、偏向電極に進行波偏向板を持つストリークカメラを用いた高速蛍光分光法の開発を行った。最終的に、装置応答関数で約8ピコ秒、計測チャンネルあたり0.2ピコ秒の時間分解能を持つシステムが得られた。 2.ラングミュア・ブロジェット膜における励起移動・励起緩和 フェルスター理論に基づく励起エネルギー移動では、移動効率はエネルギードナー・アクセプター分子間の距離とそれらの向きの関数として捕らえることができる。ラングミュア・ブロジェット(LB)法は、発色団分子を膜中にある程度の配向・距離をもって配列させることができ、エネルギー移動過程の研究に適している。 励起移動に関しては、発色団として、アントラセンとペリレンを用いた。LB膜中において、アントラセン、ペリレンの電子基底・第一励起状態間の遷移ダイポールモーメントは、それぞれ石英基板に対して60度、0度となることが知られている。また、膜1層あたりの厚さは27.5Åであり、これがアントラセン-ペリレン間距離の最短距離となる。蛍光寿命、時間分解蛍光スペクトルの測定から、平均的には40Å離れた分子間(アントラセンからペリレンヘ)で励起移動が行われていること、最短距離に配置された分子間で70ピコ秒以内でおこる励起移動が存在することが示唆された。今後、前項のシステムを用いて、高速過程の観測を行う予定である。 また、ナフタレンを含む単分子膜を生成し、その励起緩和過程を観測した。ナフタレンは、他の芳香族LB膜と比較して会合体を形成しにくいことがわかった。

  • 累積多層膜中における励起エネルギー移動とその機構
    秋本 誠志
    日本学術振興会, 科学研究費助成事業, 奨励研究(A), 北海道大学, 1994 - 1994
    LB膜はある程度配向のそろった2次元系の分子集合体であり、膜中に取り込まれた発色団は溶液などの均一分散系とは異なった光特性を示すことが知られている。本研究では、発色団としてナフタレン、アントラセンやペリレンを含んだLB膜を作製し、時間分解蛍光分光法を用いて、膜中における芳香族分子の分布および励起エネルギー緩和過程について検討した。 1.ペリレンLB膜 ペリレンLB膜の蛍光スペクトル(定常光励起、時間分解)には、溶液中で測定されるようなモノマー発光と、2種類のブロードな発光が現れる。低濃度においては主成分はモノマー発光であり、時間後期にのみブロードな発光が確認される。一方濃度が高くなると、時間初期から3つの成分がすべて現れるが、時間とともに長波長にピークを持つ成分が支配的となる。3成分の相対強度はペリレン濃度に依存し、各濃度における会合体形成や励起エネルギーの緩和過程を反映している。例えば、高濃度では、結晶中のような2量体を形成し、これが最終的なエネルギーアクセプターとして作用していることがわかった。 2.ナフタレンLB膜 α位に長鎖カルボン酸を導入したナフタレン誘導体は安定な膜を形成しにくいこと、また、ナフタレンはアントラセンやペリレンと比較して会合体を形成しにくいことがわかった。これは、ナフタレン間に斥力的相互作用が働いているか、α位に長鎖が導入されたことによる立体障害によるものと考えられる。現在、β位に長鎖カルボン酸を導入したナフタレン誘導体について研究を行っているところである。

  • Fractal Structures and Excitation Energy Relaxation in Molecular Assemblies
    YAMAZAKI Iwao, AKIMOTO Seiji, NISHIMURA Yosinobu, OHTA Nobuhiro
    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for General Scientific Research (A), Hokkaido University, Faculty of Science, 1991 - 1994
    Organic molecules in general form self-assembled organizates. Typical examples are vesicles, Langmuir-Blodgett (LB) monolayr films and liquid crystals, in which some structural orders appear with respect to molecular orientation and spatial distribution of guest molecules, and determine the macroscopic morphology of these assemblies. In this study, the structural orders have been investigated by means of the excitation energy transfer between molecules monitored with a picosecond time-resolved fluorescence spectroscopy. The spatial distribution of molecules, which can be expressed in terms of "fractal", was investigated for polymers and LB films. It was found that the fractal dimension depends on (d) types of molecules, molecular inteaction : d = 1.7 in a surface of silicagel microcrystals, d = 1.3 - 1.7 in LB films of cyanine and rhodamine dyes, and d = 1.0 - 1.4 in hydrophobic plymers. The dynamical properties of excitation energy relaxation are characterized by the energy hopping migration among sites of slightly different energies.

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