Research activity information

• Comparative analysis of lipolytic enzymes involved in the surface fermentation of dried katsuobushi by xerophilic molds

  Shinji Takenaka, Ryota Toyoshima, Tomoya Umeki, Yukihiro Kimura, Shinichi Tanaka, Jun‐ichi Matsumoto, Mikiharu Doi

  Abstract Background Fermented katsuobushi, a traditional Japanese seasoning, is produced from skipjack tuna through smoking, drying and fermentation by xerophilic Aspergillus molds, primarily Aspergillus chevalieri and Aspergillus pseudoglaucus. In this study, we characterized lipolytic enzymes (cLip_1 to cLip_5 and pLip_1 to pLip_3) to clarify their roles in lipid hydrolysis during katsuobushi production under low water activity. Results The enzymes showed significant diversity in their activity, stability and substrate specificity, and in the hydrolysis profiles of their reactions with fish oil. Phylogenetic analyses revealed that cLip_5 showed a high identity with pLip_2 (94%) and these enzymes formed a phylogenetic cluster with filamentous fungal lipases. Purified recombinant enzymes (rcLip_1, rcLip_2, rcLip_4 and rcLip_5) and wild‐type enzymes (cLip_3 and pLip_3) showed varying substrate preferences toward p‐nitrophenyl esters. The addition of glycerol to reduce the water activity in the reaction mixture led to increased activities of rcLip_1 and rcLip_4, but it did not affect the activity of the other three enzymes. Among the tested six enzymes, cLip_5 showed the highest hydrolytic activity toward fish oil. The cLip_5 and pLip_2 gene transcript levels were moderately high in strains MK86 and MK88, respectively. Conclusion cLip_5 and its homolog pLip_2 were identified as the most promising enzymes for katsuobushi fermentation, because of their high hydrolytic activities toward fish oil and adaptability to low water activity conditions. These findings support the selection of optimal Aspergillus strains as starter cultures to potentially shorten the fermentation time and improve the quality and shelf life of katsuobushi. © 2025 Society of Chemical Industry.

  Wiley, Feb. 2025, Journal of the Science of Food and Agriculture, English

  [Refereed]

  Scientific journal


• A distinct double-ring LH1–LH2 photocomplex from an extremophilic phototroph

  Kazutoshi Tani, Kenji V. P. Nagashima, Risa Kojima, Masaharu Kondo, Ryo Kanno, Issei Satoh, Mai Kawakami, Naho Hiwatashi, Kazuna Nakata, Sakiko Nagashima, Kazuhito Inoue, Yugo Isawa, Ryoga Morishita, Shinichi Takaichi, Endang R. Purba, Malgorzata Hall, Long-Jiang Yu, Michael T. Madigan, Akira Mizoguchi, Bruno M. Humbel, Yukihiro Kimura, Yutaka Nagasawa, Takehisa Dewa, Zheng-Yu Wang-Otomo

  Corresponding, Springer Science and Business Media LLC, Feb. 2025, Nature Communications, 16(1) (1), English

  [Refereed]

  Scientific journal

  Link to Kobe Univ. Repository (Kernel)


• Genomic highlights of the phylogenetically unique halophilic purple nonsulfur bacterium, Rhodothalassium salexigens

  Michael T. Madigan, Kelly S. Bender, Mary N. Parenteau, Yukihiro Kimura, Zheng-Yu Wang-Otomo, W. Matthew Sattley

  Abstract Rhodothalassium (Rts.) salexigens is a halophilic purple nonsulfur bacterium and the sole species in the genus Rhodothalassium, which is itself the sole genus in the family Rhodothalassiaceae and sole family in the order Rhodothalassiales (class Alphaproteobacteria). The genome of this phylogenetically unique phototroph comprises 3.35 Mb and is highly chimeric, with nearly half of its genes originating from families other than the Rhodothalassiaceae, many of which lack phototrophic species. Photosynthesis genes in Rts. salexigens are not arranged in a typical photosynthesis gene cluster but are scattered across the genome, suggesting an origin from horizontal transfers. Despite an encoded RuBisCO, autotrophy has not been observed in Rts. salexigens, and enzymes that oxidize common inorganic electron donors are not encoded. Phospholipid biosynthesis in Rts. salexigens is restricted, and phosphoglycerolipids are the only phospholipids present in its intracytoplasmic membranes. Rts. salexigens fixes nitrogen using a Mo-containing nitrogenase and uses ammonia despite previous results that indicated it was a glutamate auxotroph. Glycine betaine is the sole osmolyte in Rts. salexigens, and enzymes are encoded that facilitate both its uptake and its biosynthesis from glycine. The genomic data also support chemotactic swimming motility, growth over a range of salinities, and the production of membrane-strengthening hopanoids.

  Springer Science and Business Media LLC, Jan. 2025, Extremophiles, 29(1) (1)

  [Refereed]

  Scientific journal


• A Native LH1–RC–HiPIP Supercomplex from an Extremophilic Phototroph

  Kazutoshi Tani, Ryo Kanno, Kenji V. P. Nagashima, Mai Kawakami, Naho Hiwatashi, Kazuna Nakata, Sakiko Nagashima, Kazuhito Inoue, Shinichi Takaichi, Endang R. Purba, Malgorzata Hall, Long-Jiang Yu, Michael T. Madigan, Akira Mizoguchi, Bruno M. Humbel, Yukihiro Kimura, Zheng-Yu Wang-Otomo

  Corresponding, Springer Science and Business Media LLC, Jan. 2025, Communications Biology, 8(1) (1), English

  [Refereed]

  Scientific journal

  Link to Kobe Univ. Repository (Kernel)


• Insights into the divergence of the photosynthetic LH1 complex obtained from structural analysis of the unusual photocomplexes of Roseospirillum parvum

  Xiang-Ping Wang, Guang-Lei Wang, Yuan Fu, Akane Minamino, Mei-Juan Zou, Fei Ma, Bo Xu, Zheng-Yu Wang-Otomo, Yukihiro Kimura, Michael T. Madigan, Jörg Overmann, Long-Jiang Yu

  Springer Science and Business Media LLC, Dec. 2024, Communications Biology, 7(1) (1)

  [Refereed]

  Scientific journal


• The Thermal-Stable LH1–RC Complex of a Hot Spring Purple Bacterium Powers Photosynthesis with Extremely Low-Energy Near-Infrared Light

  Yukihiro Kimura, Ryo Kanno, Kaisei Mori, Yoshiki Matsuda, Ryuta Seto, Shinji Takenaka, Hiroyuki Mino, Tatsunari Ohkubo, Mai Honda, Yuji C. Sasaki, Jun-ichi Kishikawa, Kaoru Mitsuoka, Kazuhiro Mio, Malgorzata Hall, Endang R. Purba, Toshiaki Mochizuki, Akira Mizoguchi, Bruno M. Humbel, Michael T. Madigan, Zheng-Yu Wang-Otomo, Kazutoshi Tani

  American Chemical Society (ACS), Dec. 2024, Biochemistry, 64(1) (1), 170 - 179, English

  [Refereed]

  Scientific journal


• Spectral modulation of B850 bacteriochlorophyll a in light-harvesting complex 2 from purple photosynthetic bacterium Thermochromatium tepidum by detergents and calcium ions

  Yoshitaka Saga, Yuhi Sasamoto, Kazuki Inada, Zheng-Yu Wang-Otomo, Yukihiro Kimura

  Last, Elsevier BV, Aug. 2024, Biochimica et Biophysica Acta (BBA) - Bioenergetics, 149503 - 149503, English

  [Refereed]

  Scientific journal


• Structural insights into the unusual core photocomplex from a triply extremophilic purple bacterium, Halorhodospira halochloris

  Chen‐Hui Qi, Guang‐Lei Wang, Fang‐Fang Wang, Jie Wang, Xiang‐Ping Wang, Mei‐Juan Zou, Fei Ma, Michael T. Madigan, Yukihiro Kimura, Zheng‐Yu Wang‐Otomo, Long‐Jiang Yu

  ABSTRACT Halorhodospira (Hlr.) halochloris is a triply extremophilic phototrophic purple sulfur bacterium, as it is thermophilic, alkaliphilic, and extremely halophilic. The light‐harvesting‐reaction center (LH1–RC) core complex of this bacterium displays an LH1‐Q_y transition at 1,016 nm, which is the lowest‐energy wavelength absorption among all known phototrophs. Here we report the cryo‐EM structure of the LH1–RC at 2.42 Å resolution. The LH1 complex forms a tricyclic ring structure composed of 16 αβγ‐polypeptides and one αβ‐heterodimer around the RC. From the cryo‐EM density map, two previously unrecognized integral membrane proteins, referred to as protein G and protein Q, were identified. Both of these proteins are single transmembrane‐spanning helices located between the LH1 ring and the RC L‐subunit and are absent from the LH1–RC complexes of all other purple bacteria of which the structures have been determined so far. Besides bacteriochlorophyll b molecules (B1020) located on the periplasmic side of the Hlr. halochloris membrane, there are also two arrays of bacteriochlorophyll b molecules (B800 and B820) located on the cytoplasmic side. Only a single copy of a carotenoid (lycopene) was resolved in the Hlr. halochloris LH1–α3β3 and this was positioned within the complex. The potential quinone channel should be the space between the LH1–α3β3 that accommodates the single lycopene but does not contain a γ‐polypeptide, B800 and B820. Our results provide a structural explanation for the unusual Q_y red shift and carotenoid absorption in the Hlr. halochloris spectrum and reveal new insights into photosynthetic mechanisms employed by a species that thrives under the harshest conditions of any phototrophic microorganism known.

  Corresponding, Wiley, Feb. 2024, Journal of Integrative Plant Biology, English

  [Refereed]

  Scientific journal

  Link to Kobe Univ. Repository (Kernel)


• Calcium and the ecology of photosynthesis in purple sulfur bacteria

  Michael T. Madigan, W. Matthew Sattley, Yukihiro Kimura, Zheng‐Yu Wang‐Otomo

  Abstract The ecological success of purple sulfur bacteria (PSB) is linked to their ability to collect near‐infrared solar energy by membrane‐integrated, pigment–protein photocomplexes. These include a Core complex containing both light‐harvesting 1 (LH1) and reaction centre (RC) components (called the LH1–RC photocomplex) present in all PSB and a peripheral light‐harvesting complex present in most but not all PSB. In research to explain the unusual absorption properties of the thermophilic purple sulfur bacterium Thermochromatium tepidum, Ca²⁺ was discovered bound to LH1 polypeptides in its LH1–RC; further work showed that calcium controls both the thermostability and unusual spectrum of the Core complex. Since then, Ca²⁺ has been found in the LH1–RC photocomplexes of several other PSB, including mesophilic species, but not in the LH1–RC of purple non‐sulfur bacteria. Here we focus on four species of PSB—two thermophilic and two mesophilic—and describe how Ca²⁺ is integrated into and affects their photosynthetic machinery and why this previously overlooked divalent metal is a key nutrient for their ecological success.

  Wiley, Feb. 2024, Environmental Microbiology, 26(2) (2), English

  [Refereed][Invited]

  Scientific journal


• High-resolution structure and biochemical properties of the LH1–RC photocomplex from the model purple sulfur bacterium, Allochromatium vinosum

  Kazutoshi Tani, Ryo Kanno, Ayaka Harada, Yuki Kobayashi, Akane Minamino, Shinji Takenaka, Natsuki Nakamura, Xuan-Cheng Ji, Endang R. Purba, Malgorzata Hall, Long-Jiang Yu, Michael T. Madigan, Akira Mizoguchi, Kenji Iwasaki, Bruno M. Humbel, Yukihiro Kimura, Zheng-Yu Wang-Otomo

  Abstract The mesophilic purple sulfur phototrophic bacterium Allochromatium (Alc.) vinosum (bacterial family Chromatiaceae) has been a favored model for studies of bacterial photosynthesis and sulfur metabolism, and its core light-harvesting (LH1) complex has been a focus of numerous studies of photosynthetic light reactions. However, despite intense efforts, no high-resolution structure and thorough biochemical analysis of the Alc. vinosum LH1 complex have been reported. Here we present cryo-EM structures of the Alc. vinosum LH1 complex associated with reaction center (RC) at 2.24 Å resolution. The overall structure of the Alc. vinosum LH1 resembles that of its moderately thermophilic relative Alc. tepidum in that it contains multiple pigment-binding α- and β-polypeptides. Unexpectedly, however, six Ca ions were identified in the Alc. vinosum LH1 bound to certain α1/β1- or α1/β3-polypeptides through a different Ca²⁺-binding motif from that seen in Alc. tepidum and other Chromatiaceae that contain Ca²⁺-bound LH1 complexes. Two water molecules were identified as additional Ca²⁺-coordinating ligands. Based on these results, we reexamined biochemical and spectroscopic properties of the Alc. vinosum LH1–RC. While modest but distinct effects of Ca²⁺ were detected in the absorption spectrum of the Alc. vinosum LH1 complex, a marked decrease in thermostability of its LH1–RC complex was observed upon removal of Ca²⁺. The presence of Ca²⁺ in the photocomplex of Alc. vinosum suggests that Ca²⁺-binding to LH1 complexes may be a common adaptation in species of Chromatiaceae for conferring spectral and thermal flexibility on this key component of their photosynthetic machinery.

  Corresponding, Springer Science and Business Media LLC, Feb. 2024, Communications Biology, 7(1) (1), English

  [Refereed]

  Scientific journal

  Link to Kobe Univ. Repository (Kernel)


• Selective expression of light-harvesting complexes alters phospholipid composition in the intracytoplasmic membrane and core complex of purple phototrophic bacteria

  I. Satoh, K. Gotou, S. Nagatsuma, K.V.P. Nagashima, M. Kobayashi, L.-J. Yu, M.T. Madigan, Y. Kimura, Z.-Y. Wang-Otomo

  Elsevier BV, Nov. 2023, Biochimica et Biophysica Acta (BBA) - Bioenergetics, 1864(4) (4), 149001 - 149001, English

  [Refereed]

  Scientific journal


• Heterologous expression and characterization of salt-tolerant beta-glucosidase from xerophilic Aspergillus chevalieri for hydrolysis of marine biomass

  Hironori Senba, Daisuke Saito, Yukihiro Kimura, Shinichi Tanaka, Mikiharu Doi, Shinji Takenaka

  Sep. 2023, ARCHIVES OF MICROBIOLOGY, 205(9) (9), English

  [Refereed]

  Scientific journal

  Link to Kobe Univ. Repository (Kernel)


• Genomic basis for the unique phenotype of the alkaliphilic purple nonsulfur bacterium Rhodobaca bogoriensis

  Michael T. Madigan, Kelly S. Bender, Sophia A. Sanguedolce, Mary N. Parenteau, Marisa H. Mayer, Yukihiro Kimura, Zheng-Yu Wang-Otomo, W. Matthew Sattley

  Aug. 2023, EXTREMOPHILES, 27(2) (2), English

  [Refereed]

  Scientific journal


• Exploring the potential of katsuobushi grounds as a source of bioactive peptides through fermentation with Aspergillus sydowii

  Shinji Takenaka, Masaki Kato, Yasuhiro Oribe, Yukihiro Kimura, Shinichi Tanaka, Jun-ichi Matsumoto, Mikiharu Doi

  Jul. 2023, PROCESS BIOCHEMISTRY, 130, 534 - 544, English

  [Refereed]

  Scientific journal


• Improvement in salt-tolerance of Aspergillus oryzae γ-glutamyl transpeptidase via protein chimerization with Aspergillus sydowii homolog

  Hironori Senba, Arisa Nishikawa, Yukihiro Kimura, Shinichi Tanaka, Jun-ichi Matsumoto, Mikiharu Doi, Shinji Takenaka

  Elsevier BV, Apr. 2023, Enzyme and Microbial Technology, 110240 - 110240, English

  [Refereed]

  Scientific journal


• Atomic force microscopic analysis of the light-harvesting complex 2 from purple photosynthetic bacterium Thermochromatium tepidum.

  Masayuki Morimoto, Haruna Hirao, Masaharu Kondo, Takehisa Dewa, Yukihiro Kimura, Zheng-Yu Wang-Otomo, Hitoshi Asakawa, Yoshitaka Saga

  Structural information on the circular arrangements of repeating pigment-polypeptide subunits in antenna proteins of purple photosynthetic bacteria is a clue to a better understanding of molecular mechanisms for the ring-structure formation and efficient light harvesting of such antennas. Here, we have analyzed the ring structure of light-harvesting complex 2 (LH2) from the thermophilic purple bacterium Thermochromatium tepidum (tepidum-LH2) by atomic force microscopy. The circular arrangement of the tepidum-LH2 subunits was successfully visualized in a lipid bilayer. The average top-to-top distance of the ring structure, which is correlated with the ring size, was 4.8 ± 0.3 nm. This value was close to the top-to-top distance of the octameric LH2 from Phaeospirillum molischianum (molischianum-LH2) by the previous analysis. Gaussian distribution of the angles of the segments consisting of neighboring subunits in the ring structures of tepidum-LH2 yielded a median of 44°, which corresponds to the angle for the octameric circular arrangement (45°). These results indicate that tepidum-LH2 has a ring structure consisting of eight repeating subunits. The coincidence of an octameric ring structure of tepidum-LH2 with that of molischianum-LH2 is consistent with the homology of amino acid sequences of the polypeptides between tepidum-LH2 and molischianum-LH2.

  Mar. 2023, Photosynthesis research, English, International magazine

  [Refereed]

  Scientific journal


• Rhodobacter capsulatus forms a compact crescent-shaped LH1-RC photocomplex.

  Kazutoshi Tani, Ryo Kanno, Xuan-Cheng Ji, Itsusei Satoh, Yuki Kobayashi, Malgorzata Hall, Long-Jiang Yu, Yukihiro Kimura, Akira Mizoguchi, Bruno M Humbel, Michael T Madigan, Zheng-Yu Wang-Otomo

  Rhodobacter (Rba.) capsulatus has been a favored model for studies of all aspects of bacterial photosynthesis. This purple phototroph contains PufX, a polypeptide crucial for dimerization of the light-harvesting 1-reaction center (LH1-RC) complex, but lacks protein-U, a U-shaped polypeptide in the LH1-RC of its close relative Rba. sphaeroides. Here we present a cryo-EM structure of the Rba. capsulatus LH1-RC purified by DEAE chromatography. The crescent-shaped LH1-RC exhibits a compact structure containing only 10 LH1 αβ-subunits. Four αβ-subunits corresponding to those adjacent to protein-U in Rba. sphaeroides were absent. PufX in Rba. capsulatus exhibits a unique conformation in its N-terminus that self-associates with amino acids in its own transmembrane domain and interacts with nearby polypeptides, preventing it from interacting with proteins in other complexes and forming dimeric structures. These features are discussed in relation to the minimal requirements for the formation of LH1-RC monomers and dimers, the spectroscopic behavior of both the LH1 and RC, and the bioenergetics of energy transfer from LH1 to the RC.

  Feb. 2023, Nature communications, 14(1) (1), 846 - 846, English, International magazine

  [Refereed]

  Scientific journal


• Advances in the Spectroscopic and Structural Characterization of Core Light-Harvesting Complexes from Purple Phototrophic Bacteria

  Yukihiro Kimura, Kazutoshi Tani, Michael T. Madigan, Zheng-Yu Wang-Otomo

  American Chemical Society (ACS), Jan. 2023, The Journal of Physical Chemistry B, English

  [Refereed][Invited]

  Scientific journal


• Asymmetric structure of the native Rhodobacter sphaeroides dimeric LH1–RC complex

  Kazutoshi Tani, Ryo Kanno, Riku Kikuchi, Saki Kawamura, Kenji V. P. Nagashima, Malgorzata Hall, Ai Takahashi, Long-Jiang Yu, Yukihiro Kimura, Michael T. Madigan, Akira Mizoguchi, Bruno M. Humbel, Zheng-Yu Wang-Otomo

  Abstract Rhodobacter sphaeroides is a model organism in bacterial photosynthesis, and its light-harvesting-reaction center (LH1–RC) complex contains both dimeric and monomeric forms. Here we present cryo-EM structures of the native LH1–RC dimer and an LH1–RC monomer lacking protein-U (ΔU). The native dimer reveals several asymmetric features including the arrangement of its two monomeric components, the structural integrity of protein-U, the overall organization of LH1, and rigidities of the proteins and pigments. PufX plays a critical role in connecting the two monomers in a dimer, with one PufX interacting at its N-terminus with another PufX and an LH1 β-polypeptide in the other monomer. One protein-U was only partially resolved in the dimeric structure, signaling different degrees of disorder in the two monomers. The ΔU LH1–RC monomer was half-moon-shaped and contained 11 α- and 10 β-polypeptides, indicating a critical role for protein-U in controlling the number of αβ-subunits required for dimer assembly and stabilization. These features are discussed in relation to membrane topology and an assembly model proposed for the native dimeric complex.

  Springer Science and Business Media LLC, Dec. 2022, Nature Communications, 13(1) (1), 1904 - 1904, English, International magazine

  [Refereed]

  Scientific journal


• An LH1–RC photocomplex from an extremophilic phototroph provides insight into origins of two photosynthesis proteins

  Kazutoshi Tani, Ryo Kanno, Keigo Kurosawa, Shinichi Takaichi, Kenji V. P. Nagashima, Malgorzata Hall, Long-Jiang Yu, Yukihiro Kimura, Michael T. Madigan, Akira Mizoguchi, Bruno M. Humbel, Zheng-Yu Wang-Otomo

  Abstract Rhodopila globiformis is the most acidophilic of anaerobic purple phototrophs, growing optimally in culture at pH 5. Here we present a cryo-EM structure of the light-harvesting 1–reaction center (LH1–RC) complex from Rhodopila globiformis at 2.24 Å resolution. All purple bacterial cytochrome (Cyt, encoded by the gene pufC) subunit-associated RCs with known structures have their N-termini truncated. By contrast, the Rhodopila globiformis RC contains a full-length tetra-heme Cyt with its N-terminus embedded in the membrane forming an α-helix as the membrane anchor. Comparison of the N-terminal regions of the Cyt with PufX polypeptides widely distributed in Rhodobacter species reveals significant structural similarities, supporting a longstanding hypothesis that PufX is phylogenetically related to the N-terminus of the RC-bound Cyt subunit and that a common ancestor of phototrophic Proteobacteria contained a full-length tetra-heme Cyt subunit that evolved independently through partial deletions of its pufC gene. Eleven copies of a novel γ-like polypeptide were also identified in the bacteriochlorophyll a-containing Rhodopila globiformis LH1 complex; γ-polypeptides have previously been found only in the LH1 of bacteriochlorophyll b-containing species. These features are discussed in relation to their predicted functions of stabilizing the LH1 structure and regulating quinone transport under the warm acidic conditions.

  Springer Science and Business Media LLC, Nov. 2022, Communications Biology, 5(1) (1)

  [Refereed]

  Scientific journal


• Isolation and characterization of a salt-tolerant γ-glutamyl transpeptidase from xerophilic Aspergillus sydowii

  Arisa Nishikawa, Hironori Senba, Yukihiro Kimura, Satoko Yokota, Mikiharu Doi, Shinji Takenaka

  Springer Science and Business Media LLC, Oct. 2022, 3 Biotech, 12(10) (10)

  [Refereed]

  Scientific journal


• Salt- and pH-Dependent Thermal Stability of Photocomplexes from Extremophilic Bacteriochlorophyll b-Containing Halorhodospira Species

  Yukihiro Kimura, Kazuna Nakata, Shingo Nojima, Shinji Takenaka, Michael T. Madigan, Zheng-Yu Wang-Otomo

  Halorhodospira (Hlr.) species are the most halophilic and alkaliphilic of all purple bacteria. Hlr. halochloris exhibits the lowest LH1 Qy transition energy among phototrophic organisms and is the only known triply extremophilic anoxygenic phototroph, displaying a thermophilic, halophilic, and alkaliphilic phenotype. Recently, we reported that electrostatic charges are responsible for the unusual spectroscopic properties of the Hlr. halochloris LH1 complex. In the present work, we examined the effects of salt and pH on the spectroscopic properties and thermal stability of LH1-RCs from Hlr. halochloris compared with its mesophilic counterpart, Hlr. abdelmalekii. Experiments in which the photocomplexes were subjected to different levels of salt or variable pH revealed that the thermal stability of LH1-RCs from both species was largely retained in the presence of high salt concentrations and/or at alkaline pH but was markedly reduced by lowering the salt concentration and/or pH. Based on the amino acid sequences of LH1 polypeptides and their composition of acidic/basic residues and the Hofmeister series for cation/anion species, we discuss the importance of electrostatic charge in stabilizing the Hlr. halochloris LH1-RC complex to allow it to perform photosynthesis in its warm, hypersaline, and alkaline habitat.

  MDPI AG, May 2022, Microorganisms, 10(5) (5), 959 - 959, English

  [Refereed][Invited]

  Scientific journal

  Link to Kobe Univ. Repository (Kernel)


• A Ca2+-binding motif underlies the unusual properties of certain photosynthetic bacterial core light-harvesting complexes

  Kazutoshi Tani, Kazumi Kobayashi, Naoki Hosogi, Xuan-Cheng Ji, Sakiko Nagashima, Kenji V.P. Nagashima, Airi Izumida, Kazuhito Inoue, Yusuke Tsukatani, Ryo Kanno, Malgorzata Hall, Long-Jiang Yu, Isamu Ishikawa, Yoshihiro Okura, Michael T. Madigan, Akira Mizoguchi, Bruno M. Humbel, Yukihiro Kimura, Zheng-Yu Wang-Otomo

  The mildly thermophilic purple phototrophic bacterium Allochromatium tepidum provides a unique model for investigating various intermediate phenotypes observed between those of thermophilic and mesophilic counterparts. The core light-harvesting (LH1) complex from A. tepidum exhibits an absorption maximum at 890 nm and mildly enhanced thermostability, both of which are Ca2+-dependent. However, it is unknown what structural determinants might contribute to these properties. Here, we present a cryo-EM structure of the reaction center-associated LH1 complex at 2.81 Å resolution, in which we identify multiple pigment-binding α- and β-polypeptides within an LH1 ring. Of the 16 α-polypeptides, we show that six (α1) bind Ca2+ along with β1- or β3-polypeptides to form the Ca2+-binding sites. This structure differs from that of fully Ca2+-bound LH1 from Thermochromatium tepidum, enabling determination of the minimum structural requirements for Ca2+-binding. We also identified three amino acids (Trp44, Asp47, and Ile49) in the C-terminal region of the A. tepidum α1-polypeptide that ligate each Ca ion, forming a Ca2+-binding WxxDxI motif that is conserved in all Ca2+-bound LH1 α-polypeptides from other species with reported structures. The partial Ca2+-bound structure further explains the unusual phenotypic properties observed for this bacterium in terms of its Ca2+-requirements for thermostability, spectroscopy, and phototrophic growth, and supports the hypothesis that A. tepidum may represent a "transitional" species between mesophilic and thermophilic purple sulfur bacteria. The characteristic arrangement of multiple αβ-polypeptides also suggests a mechanism of molecular recognition in the expression and/or assembly of the LH1 complex that could be regulated through interactions with reaction center subunits.

  Corresponding, Elsevier BV, Apr. 2022, Journal of Biological Chemistry, 298(6) (6), 101967 - 101967, English, International magazine

  [Refereed]

  Scientific journal


• Identification of metal-sensitive structural changes in the Ca2+-binding photocomplex from Thermochromatium tepidum by isotope-edited vibrational spectroscopy

  Yukihiro Kimura, Michie Imanishi, Li Yong, Yuki Yura, Takashi Ohno, Yoshitaka Saga, Michael T Madigan, Zheng-Yu Wang-Otomo

  AIP Publishing, Feb. 2022, The Journal of Chemical Physics

  [Refereed][Invited]

  Scientific journal


• Improvement of the halotolerance of a Bacillus serine protease by protein surface engineering

  Shinji Takenaka, Airi Takada, Yukihiro Kimura, Masanori Watanabe, Ampin Kuntiya

  Wiley, Feb. 2022, Journal of Basic Microbiology, 62(2) (2), 174 - 184

  [Refereed]

  Scientific journal


• Spectral Properties of Chlorophyll f in the B800 Cavity of Light‐harvesting Complex 2 from the Purple Photosynthetic Bacterium Rhodoblastus acidophilus

  Yoshitaka Saga, Aiko Tanaka, Madoka Yamashita, Toshiyuki Shinoda, Tatsuya Tomo, Yukihiro Kimura

  Last, Jan. 2022, Photochemistry and Photobiology, 98(1) (1), 169 - 174, English

  [Refereed]

  Scientific journal


• A previously unrecognized membrane protein in the Rhodobacter sphaeroides LH1-RC photocomplex

  Kazutoshi Tani, Kenji V. P. Nagashima, Ryo Kanno, Saki Kawamura, Riku Kikuchi, Malgorzata Hall, Long-Jiang Yu, Yukihiro Kimura, Michael T. Madigan, Akira Mizoguchi, Bruno M. Humbel, Zheng-Yu Wang-Otomo

  Rhodobacter (Rba.) sphaeroides is the most widely used model organism in bacterial photosynthesis. The light-harvesting-reaction center (LH1-RC) core complex of this purple phototroph is characterized by the co-existence of monomeric and dimeric forms, the presence of the protein PufX, and approximately two carotenoids per LH1 αβ-polypeptides. Despite many efforts, structures of the Rba. sphaeroides LH1-RC have not been obtained at high resolutions. Here we report a cryo-EM structure of the monomeric LH1-RC from Rba. sphaeroides strain IL106 at 2.9 Å resolution. The LH1 complex forms a C-shaped structure composed of 14 αβ-polypeptides around the RC with a large ring opening. From the cryo-EM density map, a previously unrecognized integral membrane protein, referred to as protein-U, was identified. Protein-U has a U-shaped conformation near the LH1-ring opening and was annotated as a hypothetical protein in the Rba. sphaeroides genome. Deletion of protein-U resulted in a mutant strain that expressed a much-reduced amount of the dimeric LH1-RC, indicating an important role for protein-U in dimerization of the LH1-RC complex. PufX was located opposite protein-U on the LH1-ring opening, and both its position and conformation differed from that of previous reports of dimeric LH1-RC structures obtained at low-resolution. Twenty-six molecules of the carotenoid spheroidene arranged in two distinct configurations were resolved in the Rba. sphaeroides LH1 and were positioned within the complex to block its channels. Our findings offer an exciting new view of the core photocomplex of Rba. sphaeroides and the connections between structure and function in bacterial photocomplexes in general.

  Springer Science and Business Media LLC, Dec. 2021, Nature Communications, 12(1) (1), 6300 - 6300, English, International magazine

  [Refereed]

  Scientific journal


• Crystal structure of a photosynthetic LH1-RC in complex with its electron donor HiPIP

  Tomoaki Kawakami, Long-Jiang Yu, Tai Liang, Koudai Okazaki, Michael T. Madigan, Yukihiro Kimura, Zheng-Yu Wang-Otomo

  Corresponding, Dec. 2021, Nature Communications, 12(1) (1), English

  [Refereed]

  Scientific journal

  Link to Kobe Univ. Repository (Kernel)


• Electrostatic charge controls the lowest LH1 Q(y) transition energy in the triply extremophilic purple phototrophic bacterium, Halorhodospira halochloris

  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-BIOENERGETICS, 1862(11) (11), English

  [Refereed]

  Scientific journal


• Identification and characterization of extracellular enzymes secreted by Aspergillus spp. involved in lipolysis and lipid-antioxidation during katsuobushi fermentation and ripening

  Shinji Takenaka, Chiaki Ogawa, Mariko Uemura, Tomoya Umeki, Yukihiro Kimura, Satoko Yokota, Mikiharu Doi

  Elsevier BV, Sep. 2021, International Journal of Food Microbiology, 353, 109299 - 109299

  [Refereed]

  Scientific journal


• Photosynthetic Growth and Energy Conversion in an Engineered Phototroph Containing Thermochromatium tepidum Light-Harvesting Complex 1 and the Rhodobacter sphaeroides Reaction Center Complex

  Kenji V. P. Nagashima, Sakiko Nagashima, Masaharu Kitashima, Kazuhito Inoue, Michael T. Madigan, Yukihiro Kimura, Zheng-Yu Wang-Otomo

  Sep. 2021, BIOCHEMISTRY, 60(36) (36), 2685 - 2690, English

  [Refereed]

  Scientific journal


• Cryo-EM Structure of the Photosynthetic LH1-RC Complex from Rhodospirillum rubrum

  Kazutoshi Tani, Ryo Kanno, Xuan-Cheng Ji, Malgorzata Hall, Long-Jiang Yu, Yukihiro Kimura, Michael T. Madigan, Akira Mizoguchi, Bruno M. Humbel, Zheng-Yu Wang-Otomo

  Aug. 2021, BIOCHEMISTRY, 60(32) (32), 2483 - 2491, English

  [Refereed]

  Scientific journal


• A Novel Membrane Protein in the Rhodobacter sphaeroides LH1-RC Photocomplex

  K. Tani, K. V. P. Nagashima, R. Kanno, S. Kawamura, R. Kikuchi, M. Hall, L.-J. Yu, Y. Kimura, M. T. Madigan, A. Mizoguchi, B. M. Humbel, Z.-Y. Wang-Otomo

  We present a cryo-EM structure of the monomeric light-harvesting-reaction center (LH1-RC) core complex from photosynthetic purple bacterium Rhodobacter (Rba.) sphaeroides at 2.9 Å resolution. The LH1 complex forms a C-shaped structure composed of 14 αβ-polypeptides around the RC with a large ring opening. From the cryo-EM density map, a previously unrecognized integral membrane protein, referred to as protein-U, was identified. Protein-U has a U-shaped conformation near the LH1-ring opening and was annotated as a hypothetical protein in the Rba. sphaeroides genome. Deletion of protein-U resulted in a mutant strain that expressed a much-reduced amount of the dimeric LH1-RC, indicating an important role for protein-U in dimerization of the LH1-RC complex. PufX was located opposite protein-U on the LH1-ring opening, and both its position and conformation differed from that of previous reports of dimeric LH1-RC structures obtained at low-resolution. Twenty-six molecules of the carotenoid spheroidene arranged in two distinct configurations were resolved in the Rba. sphaeroides LH1 and were positioned within the complex to block its pores. Our findings offer a new view of the core photocomplex of Rba. sphaeroides and the connections between structure and function in bacterial photocomplexes in general.

  Cold Spring Harbor Laboratory, Jun. 2021, English

  Scientific journal


• Cryo-EM Structure of the Photosynthetic LH1-RC Complex from Rhodospirillum rubrum

  K. Tani, R. Kanno, X.-C. Ji, M. Hall, L.-J. Yu, Y. Kimura, M. T. Madigan, A. Mizoguchi, B. M. Humbel, Z.-Y. Wang-Otomo

  We present a cryo-EM structure of the light-harvesting-reaction center (LH1-RC) core complex from purple phototrophic bacterium Rhodospirillum (Rsp.) rubrum at 2.76 Å resolution. The LH1 complex forms a closed, slightly elliptical ring structure with 16 αβ-polypeptides surrounding the RC. Our biochemical analysis detected rhodoquinone (RQ) molecules in the purified LH1-RC, and the cryo-EM density map specifically positions RQ at the Q_A site in the RC. The geranylgeraniol sidechains of bacteriochlorophyll (BChl) a_G coordinated by LH1 β-polypeptides exhibit a highly homologous tail-up conformation that allows for interactions with the bacteriochlorin rings of nearby LH1 α-associated BChls a_G. The structure also revealed key protein–protein interactions in both N- and C-terminal regions of the LH1 αβ-polypeptides, mainly within a face-to-face structural subunit. Our findings enable to evaluate past experimental and computational results obtained with this widely used organism and provide crucial information for more detailed exploration of light-energy conversion, quinone transport, and structure–function relationships in pigment-protein complexes.

  Cold Spring Harbor Laboratory, May 2021


• Circular dichroism and resonance Raman spectroscopies of bacteriochlorophyll b-containing LH1-RC complexes

  Y. Kimura, T. Yamashita, R. Seto, M. Imanishi, M. Honda, S. Nakagawa, Y. Saga, S. Takenaka, L.-J. Yu, M. T. Madigan, Z.-Y. Wang-Otomo

  Springer Science and Business Media LLC, May 2021, Photosynthesis Research, 148(1-2) (1-2), 77 - 86

  [Refereed]

  Scientific journal


• Excitation Energy Transfer from Bacteriochlorophyll b in the B800 Site to B850 Bacteriochlorophyll a in Light-Harvesting Complex 2

  Yoshitaka Saga, Madoka Yamashita, Yuto Masaoka, Tsubasa Hidaka, Michie Imanishi, Yukihiro Kimura, Yutaka Nagasawa

  Mar. 2021, The Journal of Physical Chemistry B, 125(8) (8), 2009 - 2017, English

  [Refereed]

  Scientific journal


• Quinone transport in the closed light-harvesting 1 reaction center complex from the thermophilic purple bacterium Thermochromatium tepidum

  Rikako Kishi, Michie Imanishi, Masayuki Kobayashi, Shinji Takenaka, Michael T. Madigan, Zheng-Yu Wang-Otomo, Yukihiro Kimura

  Jan. 2021, Biochimica et Biophysica Acta (BBA) - Bioenergetics, 1862(1) (1), 148307 - 148307, English

  [Refereed]

  Scientific journal


• Cryo-EM structure of a Ca2+-bound photosynthetic LH1-RC complex containing multiple αβ-polypeptides

  Kazutoshi Tani, Ryo Kanno, Yuki Makino, Malgorzata Hall, Mizuki Takenouchi, Michie Imanishi, Long-Jiang Yu, Jörg Overmann, Michael T. Madigan, Yukihiro Kimura, Akira Mizoguchi, Bruno M. Humbel, Zheng-Yu Wang-Otomo

  The light-harvesting-reaction center complex (LH1-RC) from the purple phototrophic bacterium Thiorhodovibrio strain 970 exhibits an LH1 absorption maximum at 960 nm, the most red-shifted absorption for any bacteriochlorophyll (BChl) a-containing species. Here we present a cryo-EM structure of the strain 970 LH1-RC complex at 2.82 Å resolution. The LH1 forms a closed ring structure composed of sixteen pairs of the αβ-polypeptides. Sixteen Ca ions are present in the LH1 C-terminal domain and are coordinated by residues from the αβ-polypeptides that are hydrogen-bonded to BChl a. The Ca²⁺-facilitated hydrogen-bonding network forms the structural basis of the unusual LH1 redshift. The structure also revealed the arrangement of multiple forms of α- and β-polypeptides in an individual LH1 ring. Such organization indicates a mechanism of interplay between the expression and assembly of the LH1 complex that is regulated through interactions with the RC subunits inside.

  Springer Science and Business Media LLC, Dec. 2020, Nature Communications, 11(1) (1), 4955 - 4955, English, International magazine

  [Refereed]

  Scientific journal


• Characterization of surface Aspergillus community involved in traditional fermentation and ripening of katsuobushi

  Shinji Takenaka, Reina Nakabayashi, Chiaki Ogawa, Yukihiro Kimura, Satoko Yokota, Mikiharu Doi

  A soup stock made from katsuobushi is an important element of, and the basic seasoning responsible for the taste of, traditional Japanese cuisine. Fermented and ripened katsuobushi, called karebushi, is manufactured via a repeated molding process on the katsuobushi surface. Our aim was to characterize the surface Aspergillus community and their enzymes involved in the fermentation and ripening. Five dominant Aspergillus species isolated from the karebushi surface were identified-A. amstelodami, A. chevalieri, A. pseudoglaucus, A. ruber, and A. sydowii. Analyses were performed on final molding stage-samples from different manufacturers, and 1st to 4th molding stage-samples from the same manufacturer. The composition ratios of the five Aspergillus spp. varied according to the manufacturer of the karebushi. A. amstelodami and A. chevalieri tended to be detected as dominant species when the water content of the karebushi fillet was >15% and the fat content was >3.5%, respectively. In samples from a given manufacturer, the dominant species in the final molding stage tended to be A. chevalieri and A. pseudoglaucus. Mixed molds were cultured by solid-state fermentation using katsuobushi powder medium at two different water activity (aw) levels. Crude extracts from each culture showed lipase, aminopeptidase, carboxypeptidase, and protease activities. Notably, the crude extracts cultivated at 0.85 aw showed higher protease activity toward hemoglobin and lipase activity toward p-nitrophenyl palmitate than those at 0.95 aw. These hydrolytic enzymes are probably involved in decolorization of katsuobushi and lipid degradation during the long fermentative and ripening period. In addition, mixed cultures could transform 2,6-dimethoxyphenol into 1,2,3-trimethoxybenzene, previously reported as an attractive and mild flavor component. Our results may help promote the use of desirable Aspergillus spp. as starter cultures for manufacturers to stabilize and improve the quality of fermented and ripened karebushi.

  Elsevier BV, Aug. 2020, International Journal of Food Microbiology, 327, 108654 - 108654, English, International magazine

  [Refereed]

  Scientific journal


• Lycopene-Family Carotenoids Confer Thermostability on Photocomplexes from a New Thermophilic Purple Bacterium

  Ryuta Seto, Shinichi Takaichi, Toshiyuki Kurihara, Rikako Kishi, Mai Honda, Shinji Takenaka, Yusuke Tsukatani, Michael T. Madigan, Zheng-Yu Wang-Otomo, Yukihiro Kimura

  Jun. 2020, BIOCHEMISTRY, 59(25) (25), 2351 - 2358, English

  [Refereed]

  Scientific journal


• Reconstitution of 3-Acetyl Chlorophyll a into Light-Harvesting Complex 2 from the Purple Photosynthetic Bacterium Phaeospirillum molischianum

  Yoshitaka Saga, Madoka Yamashita, Michie Imanishi, Yukihiro Kimura, Yuto Masaoka, Tsubasa Hidaka, Yutaka Nagasawa

  Mar. 2020, ACS OMEGA, 5(12) (12), 6817 - 6825, English

  [Refereed]

  Scientific journal


• Characterization of an organic-solvent-stable elastase from Pseudomonas indica and its potential use in eggshell membrane hydrolysis

  Takenaka Shinji, Yokoyama Moe, Kimura Yukihiro, Yamashita Yoko, Ashida Hitoshi

  Oct. 2019, PROCESS BIOCHEMISTRY, 85, 156 - 163

  [Refereed]

  Scientific journal


• A Dual Role for Ca2+ in Expanding the Spectral Diversity and Stability of Light-Harvesting 1 Reaction Center Photocomplexes of Purple Phototrophic Bacteria

  Michie Imanishi, Mizuki Takenouchi, Shinichi Takaich, Shiori Nakagawa, Yoshitaka Saga, Shinji Takenaka, Michael T. Madigan, Joerg Overmann, Zheng-Yu Wang-Otomo, Yukihiro Kimura

  Jun. 2019, BIOCHEMISTRY, 58(25) (25), 2844 - 2852, English

  [Refereed]

  Scientific journal


• Influences of N-linked glycosylation on the biochemical properties of aspartic protease from Aspergillus glaucus MA0196

  Lim Lihui, Senba Hironori, Kimura Yukihiro, Yokota Satoko, Doi Mikiharu, Yoshida Ken-Ichi, Takenaka Shinji

  Apr. 2019, PROCESS BIOCHEMISTRY, 79, 74 - 80

  [Refereed]

  Scientific journal


• Phospholipid distributions in purple phototrophic bacteria and LH1-RC core complexes

  S. Nagatsuma, K. Gotou, T. Yamashita, L.-J. Yu, J.-R. Shen, M.T. Madigan, Y. Kimura, Z.-Y. Wang-Otomo

  Apr. 2019, Biochimica Biophysica Acta, 1860, 461 - 468

  [Refereed]


• Selective oxidation of B800 bacteriochlorophyll a in photosynthetic light-harvesting protein LH2

  Yoshitaka Saga, Kiyoshiro Kawano, Yuji Otsuka, Michie Imanishi, Yukihiro Kimura, Sayaka Matsui, Hitoshi Asakawa

  Mar. 2019, SCIENTIFIC REPORTS, 9(1) (1), 3636 - 3636, English, International magazine

  [Refereed]

  Scientific journal

  Link to Kobe Univ. Repository (Kernel)


• Reconstitution of Chlorophyll d into the Bacterial Photosynthetic Light-harvesting Protein LH2

  Yoshitaka Saga, Madoka Yamashita, Michie Imanishi, Yukihiro Kimura

  Last, Aug. 2018, CHEMISTRY LETTERS, 47(8) (8), 1071 - 1074, English

  [Refereed]

  Scientific journal


• Biochemical and Spectroscopic Characterizations of a Hybrid Light-Harvesting Reaction Center Core Complex

  Yukihiro Kimura, Kanako Hashimoto, Seiji Akimoto, Mizuki Takenouchi, Kengo Suzuki, Rikako Kishi, Michie Imanishi, Shinji Takenaka, Michael T. Madigan, Kenji V. P. Nagashima, Zheng-Yu Wang-Otomo

  Jul. 2018, BIOCHEMISTRY, 57(30) (30), 4496 - 4503, English

  [Refereed]

  Scientific journal


• C-terminal cleavage of the LH1 alpha-polypeptide in the Sr2+-cultured Thermochromatium tepidum

  Yukihiro Kimura, Tomoaki Kawakami, Teruhisa Arikawa, Yong Li, Long-Jiang Yu, Takashi Ohno, Michael T. Madigan, Zheng-Yu Wang-Otomo

  Mar. 2018, PHOTOSYNTHESIS RESEARCH, 135(1-3) (1-3), 23 - 31, English

  [Refereed]

  Scientific journal


• Probing structure-function relationships in early events in photosynthesis using a chimeric photocomplex

  Kenji V. P. Nagashima, Mai Sasaki, Kanako Hashimoto, Shinichi Takaichi, Sakiko Nagashima, Long-Jiang Yu, Yuto Abe, Kenta Gotou, Tomoaki Kawakami, Mizuki Takenouchi, Yuuta Shibuya, Akira Yamaguchi, Takashi Ohno, Jian-Ren Shen, Kazuhito Inoue, Michael T. Madigan, Yukihiro Kimura, Zheng-Yu Wang-Otomo

  Corresponding, Oct. 2017, PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 114(41) (41), 10906 - 10911, English

  [Refereed]

  Scientific journal


• Effects of Calcium Ions on the Thermostability and Spectroscopic Properties of the LH1-RC Complex from a New Thermophilic Purple Bacterium Allochromatium tepidum

  Yukihiro Kimura, Shuwen Lyu, Akira Okoshi, Koudai Okazaki, Natsuki Nakamura, Akira Ohashi, Takashi Ohno, Manami Kobayashi, Michie Imanishi, Shinichi Takaichi, Michael T. Madigan, Zheng-Yu Wang-Otomo

  May 2017, JOURNAL OF PHYSICAL CHEMISTRY B, 121(19) (19), 5025 - 5032, English

  [Refereed]

  Scientific journal


• Spectroscopic and Thermodynamic Characterization of the Metal-Binding Sites in the LH1-RC Complex from Thermophilic Photosynthetic Bacterium Thermochromatium tepidum

  Yukihiro Kimura, Yuki Yura, Yusuke Hayashi, Yong Li, Moe Onoda, Long-Jiang Yu, Zheng-Yu Wang-Otomo, Takashi Ohno

  Dec. 2016, JOURNAL OF PHYSICAL CHEMISTRY B, 120(49) (49), 12466 - 12473, English

  [Refereed]

  Scientific journal


• Structural Basis for the Unusual Q(y) Red-Shift and Enhanced Thermostability of the LH1 Complex from Thermochromatium tepidum

  Long-Jiang Yu, Tomoaki Kawakami, Yukihiro Kimura, Zheng-Yu Wang-Otomo

  Nov. 2016, BIOCHEMISTRY, 55(47) (47), 6495 - 6504, English

  [Refereed]

  Scientific journal


• The roles of C-terminal residues on the thermal stability and local heme environment of cytochrome c' from the thermophilic purple sulfur bacterium Thermochromatium tepidum

  Yukihiro Kimura, Sachiko Kasuga, Masashi Unno, Takashi Furusawa, Shinsuke Osoegawa, Yuko Sasaki, Takashi Ohno, Zheng-Yu Wang-Otomo

  Apr. 2015, PHOTOSYNTHESIS RESEARCH, 124(1) (1), 19 - 29, English

  [Refereed]

  Scientific journal


• 1P255 Thermodynamic analysis of metal-protein interaction in the light-harvesting 1 reaction center complex from purple sulfur bacteria(18B. Photobiology:Photosynthesis,Poster,The 52nd Annual Meeting of the Biophysical Society of Japan(BSJ2014))

  Kimura Yukihiro, Hayashi Yusuke, Otomo Seiu, Ohno Takashi

  The Biophysical Society of Japan General Incorporated Association, 2014, Seibutsu Butsuri, 54(1) (1), S183, English


• 1P253 Isotope-edited ATR-FTIR analysis of the light-harvesting 1 reaction center complex from thermophilic purple photosynthetic bacteria(18B. Photobiology:Photosynthesis,Poster,The 52nd Annual Meeting of the Biophysical Society of Japan(BSJ2014))

  Yura Yuki, Kimura Yukihiro, Otomo Seiu, Ohno Takashi

  The Biophysical Society of Japan General Incorporated Association, 2014, Seibutsu Butsuri, 54(1) (1), S183, English


• Examination of molecular mechanism for the enhanced thermal stability of anthocyanins by metal cations and polysaccharides

  Noriko Tachibana, Yukihiro Kimura, Takashi Ohno

  Corresponding, Jan. 2014, FOOD CHEMISTRY, 143, 452 - 458, English

  [Refereed]

  Scientific journal


• ATR-FTIR Detection of Metal-Sensitive Structural Changes in the Light-Harvesting 1 Reaction Center Complex from the Thermophilic Purple Sulfur Bacterium Thermochromatium tepidum

  Yong Li, Yukihiro Kimura, Teruhisa Arikawa, Zheng-Yu Wang-Otomo, Takashi Ohno

  Corresponding, Dec. 2013, BIOCHEMISTRY, 52(50) (50), 9001 - 9008, English

  [Refereed]

  Scientific journal


• Structure analysis and characterization of the cytochrome c-554 from thermophilic green sulfur photosynthetic bacterium Chlorobaculum tepidum

  Long-Jiang Yu, Masaki Unno, Yukihiro Kimura, Kasumi Yanagimoto, Hirozo Oh-oka, Zheng-Yu Wang-Otomo

  Dec. 2013, PHOTOSYNTHESIS RESEARCH, 118(3) (3), 249 - 258, English

  [Refereed]

  Scientific journal


• Strontium ions are functionally replaceable with calcium ions in the light-harvesting 1 reaction center core complex from Thermophilic purple sulfur bacterium Thermochromatium tepidum

  Kimura Yukihiro, Inada Yuta, Yu Long-Jiang, Ohno Takashi, Wang Zheng-Yu

  2013, Photosynthesis Research for Food, Fuel and the Future, Advanced Topics in Science and Technology in China, 105 - 109, English

  [Refereed]

  International conference proceedings


• Damage to photosystem II due to heat stress without light-driven electron flow: involvement of enhanced introduction of reducing power into thylakoid membranes

  Yoko Marutani, Yasuo Yamauchi, Yukihiro Kimura, Masaharu Mizutani, Yukihiro Sugimoto

  Aug. 2012, PLANTA, 236(2) (2), 753 - 761, English

  [Refereed]

  Scientific journal


• Structure Analysis and Comparative Characterization of the Cytochrome c ' and Flavocytochrome c from Thermophilic Purple Photosynthetiic Bacterium Thermochromatium tepidum

  Yu Hirano, Yukihiro Kimura, Hideaki Suzuki, Kunio Miki, Zheng-Yu Wang

  Lead, Aug. 2012, BIOCHEMISTRY, 51(33) (33), 6556 - 6567, English

  [Refereed]

  Scientific journal


• Metal cations modulate the bacteriochlorophyll-protein interaction in the light-harvesting 1 core complex from Thermochromatium tepidum

  Yukihiro Kimura, Yuta Inada, Tomoko Numata, Teruhisa Arikawa, Yong Li, Jian-Ping Zhang, Zheng-Yu Wang, Takashi Ohno

  Jul. 2012, BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS, 1817(7) (7), 1022 - 1029, English

  [Refereed]

  Scientific journal


• 3PT234 Hydrogen-bonding interactions between BChl-a and Trp residues in the light-harvestingl complexes from Thermochro-matium tepidum(The 50th Annual Meeting of the Biophysical Society of Japan)

  Li Yong, Kimura Yukihiro, Numata Tomoko, Inada Yuta, Arikawa Teruhisa, Otomo Seiu, Ohno Takashi

  The Biophysical Society of Japan General Incorporated Association, 2012, Seibutsu Butsuri, 52, S181, English


• 3PT233 Molecular mechanisms for the thermostabilization of cytochrome c' from the thermophilic purple sulfur bacterium Thermochromatium tepidum(The 50th Annual Meeting of the Biophysical Society of Japan)

  Kasuga Sachiko, Kimura Yukihiro, Furusawa Kei, Ohno Takashi, Otomo Seiu

  The Biophysical Society of Japan General Incorporated Association, 2012, Seibutsu Butsuri, 52, S180 - S181, English


• Plants switch photosystem at high temperature to protect photosystem II

  Yasuo Yamauchi, Yukihiro Kimura, Seiji Akimoto, Yoko Marutani, Masaharu Mizutani, Yukihiro Sugimoto

  Plants 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


• A Spectroscopic Variant of the Light-Harvesting 1 Core Complex from the Thermophilic Purple Sulfur Bacterium Thermochromatium tepidum

  Yukihiro Kimura, Yuta Inada, Long-Jiang Yu, Zheng-Yu Wang, Takashi Ohno

  May 2011, BIOCHEMISTRY, 50(18) (18), 3638 - 3648, English

  [Refereed]

  Scientific journal


• 2P288 Biosynthetic Replacement of Ca with Sr in pigment-protein complexes from thermophilic Purple Sulfur Bacterium Thermochromatium tepidum(The 48th Annual Meeting of the Biophysical Society of Japan)

  Kimura Yukihiro, Inada Yuta, Kasuga Sachiko, Sasaki Yuko, Yu Long-Jiang, Wang Zheng-Yu, Ohno Takashi

  The Biophysical Society of Japan General Incorporated Association, 2010, Seibutsu Butsuri, 50(2) (2), S133, English


• Overexpression, characterization, and crystallization of the functional domain of cytochrome c(z) from Chlorobium tepidum

  Makoto Higuchi, Yu Hirano, Yukihiro Kimura, Hirozo Oh-oka, Kunio Miki, Zheng-Yu Wang

  Oct. 2009, PHOTOSYNTHESIS RESEARCH, 102(1) (1), 77 - 84, English

  [Refereed]

  Scientific journal


• Specific Ca2+-binding motif in the LH1 complex from photosynthetic bacterium Thermochromatium tepidum as revealed by optical spectroscopy and structural modeling

  Fei Ma, Yukihiro Kimura, Long-Jiang Yu, Peng Wang, Xi-Cheng Ai, Zheng-Yu Wang, Jian-Ping Zhang

  Mar. 2009, FEBS JOURNAL, 276(6) (6), 1739 - 1749, English

  [Refereed]

  Scientific journal


• On the excitation-trap dynamics, red absorption and thermal stability of the lh1-rc complex from photosynthetic bacterium thermochromatium tepidum

  Fei Ma, Yukihiro Kimura, Long-Jiang Yu, Peng Wang, Xi-Cheng Ai, Zheng-Yu Wang, Jian-Ping Zhang

  2009, Optics InfoBase Conference Papers, English

  International conference proceedings


• Calcium Ions Are Required for the Enhanced Thermal Stability of the Light-harvesting-Reaction Center Core Complex from Thermophilic Purple Sulfur Bacterium Thermochromatium tepidum

  Yukihiro Kimura, Long-Jiang Yu, Yu Hirano, Hiroaki Suzuki, Zheng-Yu Wang

  Lead, Jan. 2009, JOURNAL OF BIOLOGICAL CHEMISTRY, 284(1) (1), 93 - 99, English

  [Refereed]

  Scientific journal


• Excitation dynamics of two spectral forms of the core complexes from photosynthetic bacterium Thermochromatium tepidum

  Fei Ma, Yukihiro Kimura, Xiao-Hui Zhao, Yi-Shi Wu, Peng Wang, Li-Min Fu, Zheng-Yu Wang, Jian-Ping Zhang

  Oct. 2008, BIOPHYSICAL JOURNAL, 95(7) (7), 3349 - 3357, English

  [Refereed]

  Scientific journal


• Calcium ions are involved in the unusual red shift of the light-harvesting 1 Q(y) transition of the core complex in thermophilic purple sulfur bacterium Thermochromatium tepidum

  Yukihiro Kimura, Yu Hirano, Long-Jiang Yu, Hiroaki Suzuki, Masayuki Kobayashi, Zheng-Yu Wang

  Lead, May 2008, JOURNAL OF BIOLOGICAL CHEMISTRY, 283(20) (20), 13867 - 13873, English

  [Refereed]

  Scientific journal


• Purification, characterization and crystallization of the core complex from thermophilic purple sulfur bacterium Thermochromatium tepidum

  Hiroaki Suzuki, Yu Hirano, Yukihiro Kimura, Shinichi Takaichi, Masayuki Kobayashi, Kunio Miki, Zheng-Yu Wang

  Aug. 2007, BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS, 1767(8) (8), 1057 - 1063, English

  [Refereed]

  Scientific journal


• Action spectrum for expression of the high intensity light-inducible Lhc-like gene Lhl4 in the green alga Chlamydomonas reinhardtii

  H Teramoto, A Ishii, Y Kimura, K Hasegawa, S Nakazawa, T Nakamura, S Higashi, M Watanabe, T Ono

  Mar. 2006, PLANT AND CELL PHYSIOLOGY, 47(3) (3), 419 - 425, English

  [Refereed]

  Scientific journal


• 2P344 Roles of calcium ions on the structural stability of the LH1-RC core complex from thermophilic purple bacterium Thermochromatium tepidum(43. Photosynthesis,Poster Session,Abstract,Meeting Program of EABS & BSJ 2006)

  Kimura yukihiro, Suzuki Hiroaki, Dao rina, Nakamura Masao, Otomo Seiu

  The Biophysical Society of Japan General Incorporated Association, 2006, Seibutsu Butsuri, 46(2) (2), S381, English


• FTIR detection of structural changes in a histidine ligand during S-state cycling of photosynthetic oxygen-evolving complex

  Y Kimura, N Mizusawa, A Ishii, T Ono

  Dec. 2005, BIOCHEMISTRY, 44(49) (49), 16072 - 16078, English

  [Refereed]

  Scientific journal


• Changes in Structural and Functional Properties of Oxygen-evolving Complex Induced by Replacement of D1-Glutamate 189 with Glutamine in Photosystem II LIGATION OF GLUTAMATE 189 CARBOXYLATE TO THE MANGANESE CLUSTER*

  Yukihiro Kimura, Naoki Mizusawa, Asako Ishii, Shigeaki Nakazawa, and Taka-aki Ono

  Sep. 2005, 280(45) (45), 37895 - 37900

  [Refereed]


• Studies on photosynthetic oxygen-evolving complex by means of Fourier transform infrared spectroscopy: calcium and chloride cofactors

  Y Kimura, K Hasegawa, T Yamanari, T Ono

  Jun. 2005, PHOTOSYNTHESIS RESEARCH, 84(1-3) (1-3), 245 - 250, English

  [Refereed]

  Scientific journal


• Water-sensitive low-frequency vibrations of reaction intermediates during S-state cycling in photosynthetic water oxidation

  Y Kimura, A Ishii, T Yamanari, TA Ono

  May 2005, BIOCHEMISTRY, 44(21) (21), 7613 - 7622, English

  [Refereed]

  Scientific journal


• Structural changes of D1 C-terminal alpha-carboxylate during S-state cycling in photosynthetic oxygen evolution

  Y Kimura, N Mizusawa, T Yamanari, A Ishii, T Ono

  Lead, Jan. 2005, JOURNAL OF BIOLOGICAL CHEMISTRY, 280(3) (3), 2078 - 2083, English

  [Refereed]

  Scientific journal


• Changes in the functional and structural properties of the Mn cluster induced by replacing the side group of the C-terminus of the D1 protein of photosystem II

  Naoki Mizusawa, Toshihiro Yamanari, Yukihiro Kimura, Asako Ishii, Shigeaki Nakazawa, Taka-Aki Ono

  Nov. 2004, Biochemistry, 43(46) (46), 14644 - 14652, English

  [Refereed]

  Scientific journal


• Impact of replacement of D1 C-terminal alanine with glycine on structure and function of photosynthetic oxygen-evolving complex

  Naoki Mizusawa, Yukihiro Kimura, Asako Ishii, Toshihiro Yamanari, Shigeaki Nakazawa, Haruhiko Teramoto, Taka-Aki Ono

  Lead, Jul. 2004, Journal of Biological Chemistry, 279(28) (28), 29622 - 29627, English

  [Refereed]

  Scientific journal


• Mid- to low-frequency Fourier transform infrared spectra of S-state cycle for photosynthetic water oxidation in Synechocystis sp PCC 6803

  T Yamanari, Y Kimura, N Mizusawa, A Ishii, TA Ono

  Corresponding, Jun. 2004, BIOCHEMISTRY, 43(23) (23), 7479 - 7490, English

  [Refereed]

  Scientific journal


• Oxidation of the Mn cluster induces structural changes of NO3- functionally bound to the Cl- site in the oxygen-evolving complex of photosystem II

  K Hasegawa, Y Kimura, T Ono

  Feb. 2004, BIOPHYSICAL JOURNAL, 86(2) (2), 1042 - 1050, English

  [Refereed]

  Scientific journal


• Changes of low-frequency vibrational modes induced by universal N-15- and C-15-isotope labeling in S-2/S-1 FTIR difference spectrum of oxygen-evolving complex

  Y Kimura, N Mizusawa, A Ishii, T Yamanari, TA Ono

  Nov. 2003, BIOCHEMISTRY, 42(45) (45), 13170 - 13177, English

  [Refereed]

  Scientific journal


• Functional and structural study on chelator-induced suppression of S-2/S-1 FTIR spectrum in photosynthetic oxygen-evolving complex

  Y Kimura, T Ono

  Oct. 2003, JOURNAL OF INORGANIC BIOCHEMISTRY, 97(2) (2), 231 - 239, English

  [Refereed]

  Scientific journal


• Mid-to-low frequency FTIR spectrum for the S-state cycling of the photosynthetic oxygen-evolution

  Ono T., Yamanari T., Kimura Y., Mizusawa N., Ishii A.

  The Biophysical Society of Japan General Incorporated Association, 2003, Seibutsu Butsuri, 43, S202, Japanese


• FTIR study of NO_3^- at Cl^- binding site in oxygen-evolving complex of photosystem II

  Hasegawa K., Kimura Y., Ono T.

  The Biophysical Society of Japan General Incorporated Association, 2003, Seibutsu Butsuri, 43, S203, Japanese


• Effects of universal ^<15>N an ^<13>C isotope labeling on low-frequency FTIR spectrum of oxygen-evolving complex

  Kimura Y., Mizusawa N., Ishii A., Ono T.

  The Biophysical Society of Japan General Incorporated Association, 2003, Seibutsu Butsuri, 43, S202, Japanese


• Chloride cofactor in the photosynthetic oxygen-evolving complex studied by Fourier transform infrared spectroscopy

  K Hasegawa, Y Kimura, TA Ono

  Nov. 2002, BIOCHEMISTRY, 41(46) (46), 13839 - 13850, English

  [Refereed]

  Scientific journal


• Characteristic changes of the S-2/S-1 difference FTIR spectrum induced by Ca2+ depletion and metal cation substitution in the photosynthetic oxygen-evolving complex

  Y Kimura, K Hasegawa, T Ono

  May 2002, BIOCHEMISTRY, 41(18) (18), 5844 - 5853, English

  [Refereed]

  Scientific journal


• 2D1445 Role of chloride in oxygen-evolving complex of photosystem II studied by FTIR spectroscopy

  Hasegawa K., Kimura Y., Ono T.

  The Biophysical Society of Japan General Incorporated Association, 2002, Seibutsu Butsuri, 42(2) (2), S108, Japanese


• 2D1430 Effects of Replacement of Ca^<2+> by Alkali and Alkali Earth Metal cations on Mn-cluster in Photosystem II Studied by FTIR Spectroscopy

  Kimura Y., Hasegawa K., Ono T.

  The Biophysical Society of Japan General Incorporated Association, 2002, Seibutsu Butsuri, 42(2) (2), S108, Japanese


• Chelator-induced disappearance of carboxylate stretching vibrational modes in S-2/S-1 FTIR spectrum in oxygen-evolving complex of photosystem II

  Y Kimura, TA Ono

  Nov. 2001, BIOCHEMISTRY, 40(46) (46), 14061 - 14068, English

  [Refereed]

  Scientific journal


• Tunneling effects on the 1,3-sigmatropic hydrogen shift in the photo-Fries rearranged intermediate of 2,4-dimethoxy-6-(p-tolyloxy)-s-triazine

  Yukihiro Kimura, Naoya Kakiuchi, Seiji Tobita, Haruo Shizuka

  Lead, Royal Society of Chemistry (RSC), 1998, Journal of the Chemical Society, Faraday Transactions, 94(20) (20), 3077 - 3085

  [Refereed]

  Scientific journal


• Kinetic Studies on the 1,2-Sigmatropic Hydrogen Shift in the Photorearranged Intermediate of N-Acetylpyrrole:  Tunneling Effects

  Yukihiro Kimura, Masataka Yamamoto, Seiji Tobita, Haruo Shizuka

  Lead, American Chemical Society (ACS), Jan. 1997, The Journal of Physical Chemistry A, 101(4) (4), 459 - 465

  [Refereed]

  Scientific journal

• Purification and characterization of a new thermophilic purple sulfur bacterium Caldichromatium japonicum

  Minamino, A, Saini, M.K, Takenaka, S, Wang-Otomo, Z.-Y, Kimura, Y

  Last, Nov. 2023, The 61th Annual Meeting of the BSJ


• 新規好熱性紅色光合成細菌Caldichromatium japonicmの特性解析

  南野朱音, M.K. Saini, 竹中慎治, 大友征宇, 木村行宏

  Last, Jun. 2023, 第29回光合成セミナー：反応中心と色素系の多様性（名古屋）, Japanese


• 紅色光合成細菌由来カルシウム結合型LH1-RC複合体の構造機能解析

  木村行宏

  Lead, Jun. 2023, 第29回光合成セミナー：反応中心と色素系の多様性（名古屋）, Japanese


• FTIR monitoring of photosynthetic quinone transport in the light-harvesting 1 reaction center complex from purple bacteria

  Nakamoto, Y, Kishi, R, Takenaka, S, Madigan, M.T, Nagashima, K.V.P, Wang-Otomo, Z.-Y, Kimura Y

  Last, Sep. 2022, The 60th Annual Meeting of the BSJ, Hakodate,, English


• Electrostatic charge controls spectral properties and thermal stabilities of LH1-RCs from triply extremophilic Halorhodospira halochloris

  Kimura, Y, Nakata, K, Nojima, S, Takenaka, S, Madigan, M.T, Wang-Otomo, Z.-Y

  Lead, Sep. 2022, The 60th Annual Meeting of the BSJ, Hakodate, English


• 紅色光合成細菌Thermochromatium tepidumのLH2タンパク質のB800バクテリオクロロフィルaの酸化による分光特性変化

  平尾遥奈, 木村行宏, 大友征宇, 佐賀佳央

  Mar. 2022, 日本化学会第102春季年会（兵庫）, Japanese


• 紅色光合成細菌Thermochromatium tepidumのLH2タンパク質に結合するB800バクテリオクロロフィルaの選択的酸化

  平尾遥奈, 木村行宏, 大友征宇, 佐賀佳央

  Sep. 2021, 第15回バイオ関連化学シンポジウム、鳥取


• 紅色光合成細菌の光捕集タンパク質LH2へ再構成したホルミル基含有クロロフィルのスペクトル特性

  田中愛子, 山下眞花, 篠田稔行, 鞆達也, 木村行宏, 佐賀佳央

  Sep. 2021, 第15回バイオ関連化学シンポジウム、鳥取, Japanese


• Thermochromatium tepidumのLH2タンパク質のB800の結合状態と全体構造の解析

  平尾遥奈, 井城ひなた, 淺川雅, 近藤政晴, 出羽毅久, 木村行宏, 大友征宇, 佐賀佳央

  Jul. 2021, 第28回光合成セミナー：反応中心と色素系の多様性、豊中, Japanese


• LH2タンパク質のB800部位へのクロロフィルb/d/fの再構成：分光特性とタンパク質との相互作用

  田中愛子, 山下眞花, 篠田稔行, 鞆達也, 木村行宏, 佐賀佳央

  Jul. 2021, 第28回光合成セミナー：反応中心と色素系の多様性、豊中, Japanese


• カロテノイド生合成系の調節による紅色細菌の熱耐性への適応

  小林拓己, 高市真一, 木村行宏, 大友征宇

  Jul. 2021, 第28回光合成セミナー：反応中心と色素系の多様性、豊中, Japanese


• 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

  Last, Jul. 2021, 第28回光合成セミナー：反応中心と色素系の多様性、豊中, Japanese


• 紅色光合成細菌のキノン輸送におけるリン脂質の寄与

  中元陽介, 岸利華子, 竹中慎治, 大友征宇, 木村行宏

  Last, Jul. 2021, 第28回光合成セミナー：反応中心と色素系の多様性、豊中, Japanese


• 紅色光合成細菌のLH12タンパク質へのホルミル基を有するクロロフィルの再構成”

  田中愛子, 山下眞花, 篠田稔行, 木村行宏, 鞆達也, 佐賀佳央

  Jun. 2021, 第47回生体分子科学討論会、兵庫, Japanese


• 好熱性紅色光合成細菌Halorhodospira halochlorisの特性解析

  能島紳吾, 小林正幸, 竹中慎治, M.T.Madaigan, 大友征宇, 木村行宏

  Sep. 2019, 日本農芸化学会 関西・中部支部2019合同神戸大会（神戸）


• 紅色光合成細菌電子伝達系におけるキノン輸送の追跡

  岸利華子, 今西三千絵, 小林正幸, 永島賢治, 竹中慎治, M.T.Madaigan, 大友征宇, 木村行宏

  Sep. 2019, 日本農芸化学会 関西・中部支部2019合同神戸大会（神戸）


• 紅色光合成細菌におけるキノン動態の解析

  岸利華子, 今西三千絵, 小林正幸, 永島賢治, 竹中慎治, M.T.Madaigam, 大友征宇, 木村行宏

  Jul. 2019, 第27回「光合成セミナー2019：反応中心と色素系の多様性」（豊中）


• 好熱性および好塩性を示す Halorhodospira halochloris由来光捕集反応中心複合体の特性解析

  能島紳吾, 小林正幸, 竹中慎治, Michael, T. Madigan, 大友征宇, 木村行宏

  Jul. 2018, 第26回「光合成セミナー2018：反応中心と色素系の多様性」（神戸）


• 光誘起FTIR分光法を用いた紅色細菌由来LH1-RC複合体におけるキノン分子の追跡

  岸利華子, 今西三千絵, 小林正幸, 永島賢治, Michael T. Madigan, 大友征宇, 木村 行宏

  Jul. 2018, 第26回「光合成セミナー2018：反応中心と色素系の多様性」（神戸）


• 紅色光合成細菌 Thiorhodovibrio Strain 970が示す異常なLH1Qyレッドシフトの起源

  今西三千絵, 竹之内瑠貴, 小林正幸, 竹中慎治, ࣭Michael T. Madigan, Jorg Overmann, 大友征宇, 木村 行宏

  Jul. 2018, 第26回「光合成セミナー2018：反応中心と色素系の多様性」（神戸）


• Monitoring of quinone reduction in the thermophilic purple bacterium Thermochromatium tedium by means of isotope-edited FTIR spectroscopy

  今西 三千絵, 岸 利華子, 小林 正幸, 大友 征宇, 木村 行宏

  Sep. 2017, 第55回日本生物物理学会年会（熊本）


• 同位体標識化された好熱性紅色細菌Thermochromatium tediumにおけるキノール分子の振動分光学的検出

  岸利華子, 今西三千絵, 小林正幸, 大野 隆, 大友征宇, 木村 行宏

  Jul. 2017, 第25回「光合成セミナー2017：反応中心と色素系の多様性」（神戸）


• FTIR 分光法を用いた好熱性紅色細菌 Thermochromatium tepidumにおける光合成電子伝達反応のモニタリング

  今西三千絵, 橋本佳奈子, 永島賢治, 小林正幸, 由良優季, 大野 隆, 大友征宇, 木村 行宏

  Mar. 2017, 第58回日本植物生理学会年会


• 好熱性紅色光合成細菌Thermochromatium tepidum 由来反応中心複合体におけるカルシウムイオンの機能的、構造的役割

  Michie Imanishi, Masayuki Kobayashi, Manami Kobayashi, Mari Matsuzaki, Yuki Yura, Takashi Ohno, Seiu Otomo, Yukihiro Kimura

  Nov. 2016, 第54回日本生物物理学会年会（東京）


• Ligation structure of the Mn cluster in photosynthetic oxygen evolving complex studied by FTIR spectroscopy

  Y Kimura, N Mizusawa, A Ishii, T Ono

  2006, PLANT AND CELL PHYSIOLOGY, 47, S28 - S28, English

  Summary international conference


• Property changes of the photosynthetic oxygen-evolving complex induced by replacement of D1-Glu189 with Gln

  N Mizusawa, Y Kimura, A Ishii, S Nakazawa, T Ono

  2006, PLANT AND CELL PHYSIOLOGY, 47, S27 - S27, English

  Summary international conference


• Carboxylate of D1 C-terminal Ala344 ligates a Mn ion that is oxidized upon S-1-to-S-2 transition and reduced upon S-3-to-S-0 transition

  N Mizusawa, Y Kimura, T Yamanari, A Ishii, T Ono

  2005, PLANT AND CELL PHYSIOLOGY, 46, S26 - S26, English

  Summary international conference


• Effects of systematic replacement of D1 C-terminal Ala344 with Asn, Asp, Gln, or Glu on the properties of photosynthetic oxygen evolving complex

  T Ono, N Mizusawa, Y Kimura, A Ishii, T Yamanari, S Nakazawa

  2005, PLANT AND CELL PHYSIOLOGY, 46, S179 - S179, English

  Summary international conference


• FTIR detection of water-sensitive low-frequency vibrational modes during photosynthetic water oxidation in photosystem II

  Y Kimura, T Yamanari, A Ishii, T Ono

  2005, PLANT AND CELL PHYSIOLOGY, 46, S26 - S26, English

  Summary international conference


• Functional implications of the D1 C-terminal α-carboxylate in photosynthetic oxygen evolution as studied by FTIR

  Mizusawa, N, Kimura, Y, Ishii, A, Yamanari, T, Ono, T, A

  2005, Photosynthesis: Fundamental Aspects to Global Perspectives, 376 - 378


• Functional and structural properties of oxygen-evolving complex in D1 C-terminal mutants

  Mizusawa, N, Kimura, Y, Ishii, A, Yamanari, T, Nakazawa, S, Teramoto, H, Ono, T, A

  2005, Photosynthesis: Fundamental Aspects to Global Perspectives, 352 - 354


• Low-frequency FTIR difference spectra for S-state cycling of photosynthetic water oxidation

  Y Kimura, T Yamanari, A Ishii, T Ono

  2004, PLANT AND CELL PHYSIOLOGY, 45, S83 - S83, English

  Summary international conference


• Characteristics of oxygen-evolving system in Synechocystis mutants on C-terminus of D1 protein of photosystem II: (2) An FTIR study

  T Yamanari, Y Kimura, N Mizusawa, A Ishii, T Ono

  2004, PLANT AND CELL PHYSIOLOGY, 45, S81 - S81, English

  Summary international conference


• Characteristic change in the Ligation structure of the Mn-cluster in photosystem II induced by Ca2+-depletion and metal chelators addition as revealed by FTIR spectroscopy

  Y Kimura, T Ono

  2002, PLANT AND CELL PHYSIOLOGY, 43, S64 - S64, English

  Summary international conference

• 紅色硫黄細菌の光合成とCa2+ カルシウムイオン欠乏環境での光合成戦略

  谷一寿, 木村行宏, 大友征宇

  Joint work, 光アライアンス・日本工業出版, Sep. 2024


• Function of Extrinsic Proteins in Stabilization of the Photosynthetic Oxygen-Evolving Complex

  Yong Li, Kimura Yukihiro, Ohno Takashi, Yamauchi Yasuo

  Joint work, InTech, 2012, English

  Scholarly book


• Photosystem at high temperature -mechanisms of adaptation and damage

  Yamauchi Yasuo, Kimura Yukihiro

  Joint work, Nova Science Publishers, 2011, English

  Scholarly book

• The LH1–RC structure of a thermophilic purple nonsulfur bacterium powers photosynthesis with extremely low-energy near-infrared light

  Yukihiro Kimura, Ryo Kanno, Kaisei Mori, Ryuta Seto, Yoshiki Matsuda, Shinji Takenaka, Hiroyuki Mino, Malgorzata Hall, Endang R. Purba, Akira Mizoguchi, Bruno M. Humbel, Michael T. Madigan, Zheng-Yu Wang-Otomo, Kazutoshi Tani

  AOICP2024, Sep. 2024, English

  Poster presentation


• Characterization of the light-harvesting 1 reaction center complex from psychrophilic purple nonsulfur bacteria

  Kazuki Inada, Seiji Akimoto, Shinji Takenaka, Michael T. Madigan, Zheng-Yu Wang-Otomo, Yukihiro Kimura

  AOICP2024, Sep. 2024, English

  Poster presentation


• The most stable LH1-RC structure from a novel thermophilic purple sulfur bacterium, Caldichromatium japonicum

  Akane Minamino, M. K. Saini, E. R. Purba, Malgorzata Hall, Shinji Takenaka, Vera Thiel, Bruno M. Humbel, Michael T. Madigan, Zheng-Yu Wang-Otomo, Kazutoshi Tani, Yukihiro Kimura

  AOICP2024, Sep. 2024, English

  Poster presentation


• Structural Basis for Enabling Photosynthesis with Extremely Low-energy Near-infrared Light in the LH1–RC Complex of a Thermophilic Purple Nonsulfur Bacterium

  Yukihiro Kimura, Ryo Kanno, Kaisei Mori, Ryuta Seto, Yoshiki Matsuda, Shinji Takenaka, Hiroyuki Mino, Malgorzata Hall, Endang R. Purba, Akira Mizoguchi, Bruno M. Humbel, Michael T. Madigan, Zheng-Yu Wang-Otomo, Kazutoshi Tani

  21st IUPAB & 62nd BSJ JOINT CONGRESS 2024, Jun. 2024, English

  Poster presentation


• Characterization of an LH1–RC photocomplex from a novel Japanese hot spring purple sulfur bacterium, Caldichromatium japonicum

  Akane Minamino, Mohit. K. Saini, Endang R. Purba, Malgorzata Hall, Shinji Takenaka, Vera Thiel, Bruno M. Humbel, Michael T. Madigan, Zheng-Yu Wang-Otomo, Kazutoshi Tani, Yukihiro Kimura

  21st IUPAB & 62nd BSJ JOINT CONGRESS 2024, Jun. 2024, English

  Poster presentation


• 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. Madiga, 大友 征宇, 木村 行宏

  第３１回 光合成セミナー２０２４：反応中心と色素系の多様性, Jun. 2024, Japanese

  Poster presentation


• 好熱性紅色硫黄細菌Caldichromatium japonicumにおけるLH1-RC耐熱化の分子機構

  南野 朱音, 竹中 慎治, Endang R. Purba, Michael T. Madiga, 大友 征宇, 谷 一寿, 木村 行宏

  第３１回 光合成セミナー２０２４：反応中心と色素系の多様性, Jun. 2024, Japanese

  Oral presentation


• B800バクテリオクロロフィルaの脱離がLH2タンパク質の構造・機能に与える影響

  川戸 翔太, 稲田 一輝, 浦上 千藍紗, 佐藤 榛一, 木村 行宏, 鬼頭 宏任, 橋本 秀樹, 佐賀 佳央

  第３１回 光合成セミナー２０２４：反応中心と色素系の多様性, Jun. 2024, Japanese

  Oral presentation


• 紅色非硫黄細菌Blastochloris tepida におけるLH1-RC複合体の構造機能解析

  森 凱世, 木村 行宏, 三野 広幸, 瀬戸 隆太, 松田 佳樹, 竹中 慎治, Endang R. Purba, Michael T. Madiga, 大友 征宇, 谷 一寿

  第３１回 光合成セミナー２０２４：反応中心と色素系の多様性, Jun. 2024, Japanese

  Poster presentation


• Purification and characterization of a new thermophilic purple sulfur bacterium Caldichromatium japonicum

  Akane Minamino, M. K. Saini, Shinji Takenaka, Zheng-Yu Wang-Otomo, Yukihiro Kimura

  The 60th Annual Meeting of the BSJ, Nov. 2023, English

  Poster presentation


• 紅色光合成細菌のLH2タンパク質のB800バクテリオクロロフィルaの脱離：タンパク質への影響の解析

  川戸翔太, 稲田一輝, 木村行宏, 佐賀佳央

  第23回日本光生物学協会年会, Aug. 2023, Japanese

  Poster presentation


• 紅色光合成細菌由来カルシウム結合型LH1-RC複合体の構造機能解析

  木村行宏

  第30回 光合成セミナー 2023年6月, Jun. 2023, Japanese

  [Invited]

  Invited oral presentation


• 新規好熱性紅色光合成細菌Caldichromatium japonicumの特性解析

  南野朱音, M, K. Saini, 竹中慎治, 大友征宇, 木村行宏

  第30回 光合成セミナー 2023年6月, Jun. 2023, Japanese

  Poster presentation


• Cryo-EM structure of a LH1–RC Photocomplex from an Extremophilic Phototroph

  谷 一寿, 菅野 亮, 黒澤 慧吾, 高市 真一, 永島 賢治, Malgorzata Hall, 于 龍江, 木村 行宏, Michael T. Madigan, 溝口 明, Bruno M. Humbel, 大友 征宇

  第45回 日本分子生物学会年会


• FTIR monitoring of photosynthetic quinone transport in the light-harvesting 1 reaction center complexes from purple bacteria

  Yosuke Nakamoto, Rikako Kishi, Shinji Takenaka, Michael T. Madigan, Kenji V, P. Nagashima, Zheng-Yu Wang-Otomo, Yukihiro Kimura

  The 60th Annual Meeting of the BSJ, Sep. 2022

  Poster presentation


• Electrostatic charge controls spectral properties and thermal stabilities of LH1-RCs from triply extremophilic Halorhodospira halochloris

  Yukihiro Kimura, Kazuna Nakata, Shingo Nojima, Shinji Takenaka, Michael T. Madigan, Zheng-Yu Wang-Otomo

  The 60th Annual Meeting of the BSJ, Sep. 2022

  Poster presentation


• 紅色光合成細菌Thermochromatium tepidumのLH2タンパク質に結合するバクテリオクロロフィルaの化学酸化と光酸化

  平尾 遥奈, 木村 行宏, 大友 征宇, 佐賀 佳央

  第16回バイオ関連化学シンポジウム, Sep. 2022

  Oral presentation


• 好極限性紅色細菌Halorhodospira halochlorisにおける低エネルギー吸収特性および３重耐性の分子機構

  中田和菜、能島紳吾、竹中慎治、Madigan, M.T.、大友征宇、木村行宏

  第29回 光合成セミナー, Jul. 2022

  Oral presentation


• 紅色光合成細菌の光捕集タンパク質LH2へ再構成したホルミル基含有クロロフィルのスペクトル特性

  田中愛子, 山下眞花, 篠田稔行, 鞆達也, 木村行宏, 佐賀佳央

  第15回バイオ関連化学シンポジウム, Sep. 2021


• 紅色光合成細菌Thermochromatium tepidumのLH2タンパク質に結合するB800バクテリオクロロフィルaの選択的酸化

  平尾遥奈, 木村行宏, 大友征宇, 佐賀佳央

  第15回バイオ関連化学シンポジウム, Sep. 2021


• 紅色光合成細菌のキノン輸送におけるリン脂質の寄与

  中元陽介, 岸利華子, 竹中慎治, 大友征宇, 木村行宏

  第28回光合成セミナー：反応中心と色素系の多様性, Jul. 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

  第28回光合成セミナー：反応中心と色素系の多様性, Jul. 2021


• カロテノイド生合成系の調節による紅色細菌の熱耐性への適応

  小林拓己, 高市真一, 木村行宏, 大友征宇

  第28回光合成セミナー：反応中心と色素系の多様性, Jul. 2021


• LH2タンパク質のB800部位へのクロロフィルb/d/fの再構成：分光特性とタンパク質との相互作用

  田中愛子, 山下眞花, 篠田稔行, 鞆達也, 木村行宏, 佐賀佳央

  第28回光合成セミナー：反応中心と色素系の多様性, Jul. 2021


• Thermochromatium tepidumのLH2タンパク質のB800の結合状態と全体構造の解析

  平尾遥奈, 井城ひなた, 淺川雅, 近藤政晴, 出羽毅久, 木村行宏, 大友征宇, 佐賀佳央

  第28回光合成セミナー：反応中心と色素系の多様性, Jul. 2021


• Oxidation of B800 Bacteriochlorophyll a in LH2 Protein from the Purple Photosynthetic Bacterium Thermochromatium tepidum

  Hirao, H, Kimura, Y, Wang-Otomo, Z-.Y. Saga

  SNCPP21


• 紅色光合成細菌のLH12タンパク質へのホルミル基を有するクロロフィルの再構成

  田中愛子, 山下眞花, 篠田稔行, 木村行宏, 鞆達也, 佐賀佳央

  第47回生体分子科学討論会, Jun. 2021


• 好熱性紅色光合成細菌Halorhodospira halochlorisの特性解析

  能島紳吾, 小林正幸, 竹中慎治, M.T. Madigan, 大友征宇, 木村行宏

  日本農芸化学会 関西・中部支部2019合同神戸大会, Sep. 2019, Japanese, 神戸


• バクテリオクロロフィルbを有する好熱性紅色細菌Blastochloris tepidaの耐熱性獲得機構

  瀬戸隆太, 川上知朗, 岸利華子, 今西三千絵, 高市真一, 竹中慎治, M.T. Madigan, 大友征宇, 木村行宏

  日本農芸化学会 関西・中部支部2019合同神戸大会, Sep. 2019, Japanese, 神戸


• 紅色光合成細菌電子伝達系におけるキノン輸送の追跡

  岸利華子, 今西三千絵, 小林正幸, 永島賢治, 竹中慎治, M.T. Madigan, 大友征宇, 木村行宏

  日本農芸化学会 関西・中部支部2019合同神戸大会, Sep. 2019, Japanese, 神戸


• 新規好熱性紅色細菌Blastochloris tepida由来LH1-RCの耐熱化機構と低エネルギー吸収特性の要因

  瀬戸隆太, 川上知朗, 岸利華子, 今西三千絵, 高市真一, 竹中慎治, M.T. Madigan, 大友征宇, 木村行宏

  第27回光合成セミナー：反応中心と色素系の多様性, Jul. 2019, Japanese, 豊中


• 紅色光合成細菌におけるキノン動態の解析”、第27回光合成セミナー：反応中心と色素系の多様性

  岸利華子, 今西三千絵, 小林正幸, 永島賢治, 竹中慎治, M.T. Madigan, 大友征宇, 木村行宏

  第27回光合成セミナー：反応中心と色素系の多様性, Jul. 2019, Japanese, 豊中


• 紅色光合成細菌由来光捕集１反応中心複合体のスペクトル多様性と構造安定性におけるカルシウムイオンの役割

  今西三千絵, 竹之内瑞貴, 高市真一, 中川支央里, 佐賀佳央, 竹中慎治, M.T. Madigan, 大友征宇, 木村行宏

  第27回光合成セミナー：反応中心と色素系の多様性, Jul. 2019, Japanese, 豊中


• Product analysis of electrochemical oxidation of polyphenols

  Matsumoto Kenji, HOTTA HIROKI, Kimura Yukihiro, Osakai Toshiyuki

  日本化学会第99春季年会, Mar. 2019, English, 甲南大学, Domestic conference

  Oral presentation


• A dual role for calcium in expanding the spectral diversity and stability of LH1-RC photocomplexes of purple phototrophic bacteria

  Imanishi, M, Takenouchi, M, Takaichi, S, Nakagawa, S, Saga, Y, Takenaka, S, Madigan, M.T, Overmann, J, Wang-Otomo, Z.-Y, Kimura, Y

  The 57th Annual Meeting of the BSJ, 2019, English, Miyazaki


• Spectroscopic characterization of a bacteriochlorophyll b-based LH1-RC complexes from thermophilic purple bacterium Blastochloris tepida

  Kimura, Y, Seto, R, Kishi, R, Imanishi, M, Takaichi, S, Takenaka, S, Madigan, M.T, Wang-Otomo, Z.-Y

  The 57th Annual Meeting of the BSJ, 2019, English, Miyazaki


• ポリフェノールの電解酸化機構の解明

  Matsumoto Kenji, HOTTA HIROKI, Kimura Yukihiro, Osakai Toshiyuki

  若手フロンティア研究会, Dec. 2018, Japanese, 神戸大学百年記念館, Domestic conference

  Poster presentation


• 全電解-HPLCによるポリフェノール電解酸化機構の比較

  松本 健嗣, HOTTA HIROKI, KIMURA YUKIHIRO, OSAKAI TOSHIYUKI

  第64回ポーラログラフィーおよび電気分析化学討論会, Nov. 2018, Japanese, 壱岐の島ホール（長崎県）, Domestic conference

  Poster presentation


• ポリフェノールの電解酸化生成物の比較

  Matsumoto Kenji, Hotta Hiroki, Fukushi Keiichi, Kimura Yukihiro, Osakai Toshiyuki

  日本分析化学会第68年会, Sep. 2018, Japanese, 日本分析化学会, 東北大学, Domestic conference

  Oral presentation


• Where is the quinone gate in purple photosynthetic bacterial LH1-RC complex?

  Zheng-Yu Wang-Otomo, Yukihiro Kimura

  The 56th Annual Meeting of the BSJ, Sep. 2018, English, Okayama, Domestic conference

  Nominated symposium


• Origin of the anomalous uphill energy gap in the light-harvesting reaction center from purple photosynthetic bacterium strain 970

  Michie Imanishi, Masayuki Kobayashi, Shinji Takenaka, M. T. Madigan, Zheng-Yu Wang-Otomo, Yukihiro Kimura

  The 56th Annual Meeting of the BSJ, Sep. 2018, English, Okayama, Domestic conference

  Oral presentation


• Light-induced FTIR spectroscopic studies on quinone exchange mechanism of the LH1-RC complexes from native and chimeric purple bacteria

  Rikako Kishi, Michie Imanishi, Kanako Hashimoto, V.P.K Nagashima, Masayuki Kobayashi, Shinji Takenaka, Zheng-Yu Wang-Otomo, Yukihiro Kimura

  The 56th Annual Meeting of the BSJ, Sep. 2018, English, Okayama, Domestic conference

  Poster presentation


• ポリフェノールの電解酸化機構の解明

  Matsumoto Kenji, Hotta Hiroki, Kimura Yukihiro, Osakai Toshiyuki

  日本分析化学会中部支部・近畿支部合同夏期セミナー, Aug. 2018, Japanese, 日本分析化学会, 福井大学, Domestic conference

  Poster presentation


• 同位体標識化された好熱性紅色硫黄細菌由来LH1-RC複合体の振動分光学的解析

  木村行宏, 今西三千絵, 永麗, OHNO TAKASHI, 中川支央里, 佐賀佳央, M.T. Madigan, 大友征宇

  第26回光合成セミナー：反応中心と色素系の多様性, Jul. 2018, Japanese, 神戸, Domestic conference

  Poster presentation


• 紅色光合成細菌Thiorhodovibrio Strain 970が示す異常なLH1 Qyレッドシフトの起源

  今西三千絵, 竹之内瑞貴, 小林正幸, 竹中慎治, M.T. Madigan, J. Overmann, 大友征宇, 木村行宏

  第26回光合成セミナー：反応中心と色素系の多様性, Jul. 2018, Japanese, 神戸, Domestic conference

  Oral presentation


• 好熱性および好塩性を示すHalorhodospira halochloris由来光捕集反応中心複合体の特性解析

  能島紳吾, 小林正幸, 竹中慎治, M.T. Madigan, 大友征宇, 木村行宏

  第26回光合成セミナー：反応中心と色素系の多様性, Jul. 2018, Japanese, 神戸, Domestic conference

  Poster presentation


• 光誘起FTIR分光法を用いた紅色細菌由来LH1-RC複合体におけるキノン分子の追跡

  岸利華子, 今西三千絵, 小林正幸, 永島賢治, TAKENAKA SHINJI, M.T. Madigan, 大友征宇, 木村行宏

  第26回光合成セミナー：反応中心と色素系の多様性, Jul. 2018, Japanese, 神戸, Domestic conference

  Poster presentation


• LH2タンパク質のB800バクテリオクロロフィルaのクロリン環色素への置換

  山下眞花, 大塚悠史, 川野聖志朗, 今西三千絵, 木村行宏, 佐賀佳央

  第26回光合成セミナー：反応中心と色素系の多様性, Jul. 2018, Japanese, 神戸, Domestic conference

  Oral presentation


• ヘリオバクテリア膜の光駆動キノン還元反応をFTIR法により検出する試み

  小島理沙, 岸利華子, 木村行宏, 大岡宏造

  第9回日本光合成学会, May 2018, Japanese, 仙台, Domestic conference

  Poster presentation


• カフェイン酸の電解酸化に伴う再還元能獲得に対する溶媒の影響

  Matsumoto Kenji, Hotta Hiroki, Kimura Yukihiro, Osakai Toshiyuki

  第78回分析化学討論会, May 2018, Japanese, 日本分析化学会, 山口大学, Domestic conference

  Oral presentation


• BChl bをもつ好熱性紅色非硫黄細菌Blastochloris tepida由来LH1-RCの特性評価

  川上知朗, 鈴木駿平, 本田舞, 竹之内瑞貴, 高市真一, 塚谷祐介, 木村行宏, M.T. Madigan, 大友征宇

  第9回日本光合成学会, May 2018, Japanese, 仙台, Domestic conference

  Poster presentation


• 963 nmにQy遷移をもつ紅色細菌Thiorhodovibrio strain 970由来LH1-RCの特性評価

  竹之内瑞貴, 川上知朗, 高市真一, 木村行宏, M.T. Madigan, J. Overmann, 大友征宇

  第9回日本光合成学会, May 2018, Japanese, 仙台, Domestic conference

  Poster presentation


• カフェイン酸の電解酸化機構の解析

  Matsumoto Kenji, KIMURA YUKIHIRO, OSAKAI TOSHIYUKI, 山崎 祥子, HOTTA HIROKI

  第63回ポーラログラフィーおよび電気分析化学討論会, Nov. 2017, Japanese, 海峡メッセ下関, Domestic conference

  Oral presentation


• カフェイン酸の電解酸化機構の解明

  Matsumoto Kenji, HOTTA HIROKI, KIMURA YUKIHIRO, OSAKAI TOSHIYUKI

  日本分析化学会第66年会, Sep. 2017, Japanese, 東京理科大学, Domestic conference

  Oral presentation


• Monitoring of quinone reduction in the thermophilic purple bacterium Thermochromatium tedium by means of isotope-edited FTIR spectroscopy

  Imanishi Michie, Kishi Rikako, Zheng-Yu Wang-Otomo, Kimura Yukihiro

  The 55nd Annual Meeting of the BSJ, Sep. 2017, English, Kumamoto, Domestic conference

  Oral presentation


• Co-crystallization of a bacterial photosynthetic electron-transfer complex

  Kawakami T, Liang, T, Okazaki, K, Kimura Yukihiro, Wang Zheng-Yu

  The 55th Annual Meeting of the BSJ, Sep. 2017, English, Kumamoto, Domestic conference

  Poster presentation


• 同位体標識化された好熱性紅色細菌Thermochromatium tediumにおけるキノール分子の振動分光学的検出

  岸利華子, 今西三千絵, 小林正幸, Ohno Takashi, 大友征宇, Kimura Yukihiro

  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

  Poster presentation


• 新規好熱性紅色細菌Allochromatium tepidum由来LH1-RC複合体におけるCa依存型耐熱化機構のATR-FTIR分析

  能島伸吾, 今西三千絵, 呂淑文, 小林愛実, Ohno Takashi, 大友征宇, Kimura Yukihiro

  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

  Poster 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


• Spectroscopic and thermodynamic analyses of the LH1-RC complexes from a new thermophilic purple bacterium Allochromatium tepidu

  Shuwen Lyu, Imanishi Michie, Nojima Shingo, Manami Kobayashi, Ohno Takashi, Zheng-Yu Wang-Otomo, Kimura Yukihiro

  the 5th Awaji International Workshop on Electron Spin Science & Technology, Jun. 2017, English, Awaji, Hyogo, International conference

  [Invited]

  Invited oral presentation


• Spectroscopic and thermodynamic characterization of LH1-RC complexes from Thermophilic purple bacteria

  Kimura Yukihiro

  8th OCARINA International Symposium, Mar. 2017, English, Osaka, International conference

  [Invited]

  Invited oral presentation


• FTIR 分光法を用いた好熱性紅色細菌 Thermochromatium tepidumにおける光合成電子伝達反応のモニタリング

  今西三千絵, 橋本佳奈子, 永島賢治, 小林正幸, 由良優季, Ohno Takashi, 大友征宇, Kimura Yukihiro

  第58回日本植物生理学会年会, Mar. 2017, Japanese, 鹿児島, Domestic conference

  Oral presentation


• 新規好熱性紅色光合成細菌Allochromatium tepidum由来LH1-RCの耐熱性制御機構

  呂淑文, 大友征宇, M.T. Madigan, Kimura Yukihiro, 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


• 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


• 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


• Purification and spectroscopic characterization of the light-harvesting complexes from thermophilic purple bacterium Allochromatium tepidum

  Nakamura Natsuki, Lyu Shuwen, Okoshi Kei, Okazaki Kodai, Kawakami Tomoaki, M.T. Madigan, Wang Zheng-Yu, Kimura Yukihiro

  The 54nd Annual Meeting of the BSJ, Nov. 2016, English, Tsukuba, Domestic conference

  Poster presentation


• Functional and structural roles of calcium ion in the reaction center complex from thermophilic purple photosynthetic bacterium

  Imanishi Michie, Kobayashi Manami, Kobayashi Masayuki, Matsuzaki Mari, Yura Yuki, Ohno Takashi, Wang Zheng-Yu, Kimura Yukihiro

  The 54nd Annual Meeting of the BSJ, Nov. 2016, English, Tsukuba, Domestic conference

  Poster presentation


• Spectroscopic and thermodynamic characterization of the metal-binding sites in the LH1-RC complex from thermophilic purple sulfur bacterium Thermochromatium tepidum

  Kimura Yukihiro, Yura Yuki, Hayashi Yusuke, Yong Li, Onoda Moe, Wang Zheng-Yu, Ohno Takashi

  17th International Congress on Photosynthesis, Aug. 2016, English, Maastricht, The Netherlands, International conference

  Poster presentation


• Crystal structures reveal molecular basis for the bacterial LH1 Qy transition and its thermostability

  Wang Zheng-Yu, Yu Long-Jian, Kawakami Tomoaki, Kimura Yukihiro

  17th International Congress on Photosynthesis, Aug. 2016, English, Maastricht, The Netherlands, International conference

  Poster presentation


• Characterization of the LH complexes from a new thermophilic purple bacterium Allochromatium tepidum

  Kawakami Tomoaki, Nakamura Natsuki, Kimura Yukihiro, Okazaki Kodai, Okoshi Kei, M.T. Madigan, Wang Zheng-Yu

  Light-harvesting satellite meeting of 17th International Congress on Photosynthesis, Aug. 2016, English, Egmond aan Zee, The Netherlands, International conference

  Poster presentation


• Characterization of the LH complexes from a new thermophilic purple bacterium Allochromatium tepidum

  Kawakami Tomoaki, Nakamura Natsuki, Kimura Yukihiro, Okazaki Kodai, Okoshi Kei, M.T. Madigan, Wang Zheng-Yu

  17th International Congress on Photosynthesis, Aug. 2016, English, Maastricht, The Netherlands, International conference

  Poster presentation


• 新規好熱性紅色硫黄細菌Allochromatium tepidum由来LH1-RCの特性解析

  Lyu Shuwen, Kimura Yukihiro, Ohno Takashi, M.T. Madigan, Wang Zheng-Yu

  第24回光合成セミナー：反応中心と色素系の多様性, Jul. 2016, Japanese, 京都, Domestic conference

  Poster presentation


• 888nmにQy遷移をもつ紅色細菌LH1の構造解析

  于龍江, 川上知朗, Kimura Yukihiro, Wang Zheng-Yu

  第24回光合成セミナー：反応中心と色素系の多様性, Jul. 2016, Japanese, 京都, Domestic conference

  Oral presentation


• Effects of metal cations on charge separated states of the reaction center from thermophilic purple photosynthetic bacterium Thermochromatium tepidum

  Kimura Yukihiro, Matsuzaki Mari, Yura Yuki, Wang Zheng-Yu, Ohno Takashi

  The 4th Awaji International Workshop on Electron Spin Science & Technology, Jun. 2016, English, Awaji, Hyogo, International conference

  Poster presentation


• 好熱性紅色細菌Thermochromatium tepidum由来光捕集1反応中心複合体における 吸収特性および耐熱性制御の分子機構

  Kimura Yukihiro, Yura Yuki, Yong Li, Ohno Takashi, Wang Zheng-Yu

  植物生理学会年会 第一回光合成細菌ワークショップ, Mar. 2016, Japanese, 盛岡, Domestic conference

  [Invited]

  Invited oral presentation


• Analysis of Molecular Mechanism for the Enhanced Stability of Flavonoid Compounds

  Urabe Ayaka, Kimura Yukihiro, Otake Haruka, Ohno Takashi

  The 96th Annual Meeting 2016 of CSJ, Mar. 2016, English, Kyoto, Domestic conference

  Poster presentation


• Molecular mechanisms for enhanced thermal and light stabilities of flavonoids by metal cations and polysaccharides

  Ohno Takashi, Tachibana Noriko, Urabe Ayaka, Otake Haruka, Kimura Yukihiro

  The International Chemical Congress of Pacific Basin Societies, Honolulu, Dec. 2015, English, International conference

  Poster presentation


• Towards elucidating the unusual absorption behavior and enhanced thermostability of the LH1-RC complex from Thermochromatium tepidum

  Kawakami Tomoaki, Yu L.-J, Kimura Yukihiro, Wang Zheng-Yu

  The 53nd Annual Meeting of the BSJ, Sep. 2015, English, Kanazawa, Domestic conference

  Poster presentation


• Monitoring of metal-binding sites and metal-protein interactions in the LH1-RC complex from thermophilic purple photosynthetic bacteria

  Yura Yuki, Kimura Yukihiro, Hayashi Yusuke, Yong Li, Onoda Moe, Wang Zheng-Yu, Ohno Takashi

  The 53nd Annual Meeting of the BSJ, Sep. 2015, English, Kanazawa, Domestic conference

  Poster presentation


• Molecular mechanisms for the enhanced thermal stability of LH1-RC complex from Thermochromatium tepidum: isotope-edited FTIR spectroscopy

  Kimura Yukihiro, Yura Yuki, Yong Li, Wang Zheng-Yu, Ohno Takashi

  The 53nd Annual Meeting of the BSJ, Sep. 2015, English, Kanazawa, Domestic conference

  Poster presentation


• Detection of quinone molecules in the LH1-RC complex from the thermophilic purple photosynthetic bacterium Thermochromatium tepidum

  Matsuzaki Mari, Yura Yuki, Ohno Takashi, Wang Zheng-Yu, Kimura Yukihiro

  The 53nd Annual Meeting of the BSJ, Sep. 2015, English, Kanazawa, Domestic conference

  Poster presentation


• 好熱性紅色細菌Thermochromatium tepidum由来光捕集１反応中心複合体におけるCa2+結合サイトの特性解析

  Kimura Yukihiro, Yura Yuki, Yong Li, Ohno Takashi, Wang Zheng-Yu

  第23回光合成セミナー：反応中心と色素系の多様性, Jul. 2015, Japanese, 京都, Domestic conference

  Oral presentation


• Thermodynamic analysis of metal-protein interaction in the light-harvesting 1 reaction center complex from purple sulfur bacteria

  Kimura Yukihiro, Hayashi Yusuke, Wang Zheng-Yu, Ohno Takashi

  The 52nd Annual Meeting of the BSJ, Sep. 2014, English, Sapporo, Hokkaido, Domestic conference

  Poster presentation


• Isotope-edited ATR-FTIR analysis of light-harvesting 1 reaction center complex from thermophilic purple photosynthetic bacteria

  Yura Yuki, Kimura Yukihiro, Wang Zheng-Yu, Ohno Takashi

  The 52nd Annual Meeting of the BSJ, Sep. 2014, English, Sapporo, Hokkaido, Domestic conference

  Poster presentation


• 同位体置換された好熱性紅色細菌Thermochromatium tepidum由来光捕集１反応中心複合体の振動分光学的解析

  Kimura Yukihiro, Yura Yuki, Yong Li, Wang Zheng-Yu, Ohno Takashi

  第２２回光合成セミナー：反応中心と色素系の多様性, Jul. 2014, Japanese, 名古屋, Domestic conference

  Poster presentation


• 好熱性紅色細菌由来光捕集１反応中心複合体のメタロミクス解析

  Hayashi Yusuke, Kimura Yukihiro, Wang Zheng-Yu, Ohno Takashi

  第２２回光合成セミナー：反応中心と色素系の多様性, Jul. 2014, Japanese, 名古屋, Domestic conference

  Poster presentation


• Metal cations modulate protein conformation and thermal stability of light-harvesting 1 reaction center complexes from purple sulfur photosynthetic bacteria

  Kimura Yukihiro, Yura Yuki, Yong Li, Wang Zheng-Yu, Ohno Takashi

  The 2nd Awaji International Workshop on Electron Spin Science & Technology, Jun. 2014, English, Awaji, Hyogo, International conference

  [Invited]

  Invited oral presentation


• 鉄(III)及び酸性多糖類共存系におけるアントシアニンの耐久性及び機能評価

  Tachibana Noriko, Kimura Yukihiro, Ohno Takashi

  日本化学会第93春季年会, Mar. 2013, Japanese, Domestic conference

  Oral presentation


• 全反射吸収赤外分光法による紅色硫黄光合成細菌Thermochromatium tepidum由来光捕集1膜蛋白質複合体の構造解析”、 日本化学会第93春季年会

  Yong Li, Kimura Yukihiro, Wang Zheng-Yu, Ohno Takashi

  日本化学会第93春季年会, Mar. 2013, Japanese, Domestic conference

  Oral presentation


• 好熱性紅色細菌由来光捕集1反応中心複合体の耐熱化を制御する構造変化の振動分光学的検出

  Kimura Yukihiro, Yong Li, Arikawa Teruhisa, Wang Zheng-Yu, Ohno Takashi

  第20回光合成の色素系と反応中心に関するセミナー, 2013, Japanese, Domestic conference

  Oral presentation


• Molecular mechanisms for the enhanced thermal stability and unusually red-shifted Qy transition of light-harvesting 1 complexes from thermophilic purple sulfur bacterium Thermochromatium tepidum as revealed by vibrational spectroscopy

  Kimura Yukihiro, Yong Li, Arikawa Teruhisa, Inada Yuta, Wang Zheng-Yu, Ohno Takashi

  16th International Congress on Photosynthesis, 2013, English, International conference

  Poster presentation


• 灌流誘起赤外分光法による光合成膜蛋白質複合体の構造解析

  Yong Li, Kimura Yukihiro, Ohno Takashi

  第473回日本農芸化関西支部講演会, 2012, Japanese, Domestic conference

  Oral 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


• 紅色硫黄細菌由来光捕集1複合体における色素—蛋白質相互作用の解析

  Kimura Yukihiro, Yong Li, Arikawa Teruhisa, Mumata Tomoko, Wang Zheng-Yu, Ohno Takashi

  第20回光合成の色素系と反応中心に関するセミナー, 2012, Japanese, Domestic conference

  Oral presentation


• 紅色硫黄光合成細菌由来cytochrome c’の熱安定性におけるC末端近傍アミノ酸残基の影響

  Kasuga Sachiko, Kimura Yukihiro, Furusawa Kei, Ohno Takashi, Wang Zheng-Yu

  日本化学会第92春季年会, 2012, Japanese, Domestic conference

  Poster presentation


• 好熱性紅色硫黄細菌Thermochromatium tepidum由来光捕集１複合体におけるBChl-aとTrp残基間の水素結合相互作用

  Yong Li, Kimura Yukihiro, Mumata Tomoko, Inada Yuta, Arikawa Teruhisa, Wang Zheng-Yu, Ohno Takashi

  第50回日本生物物理学会年会, 2012, English, Domestic conference

  Poster presentation


• 好熱性紅色硫黄細菌Thermochromatium tepidum由来cytochrome c’における耐熱化メカニズムの検討

  Kasuga Sachiko, Kimura Yukihiro, 古澤 敬, Ohno Takashi, Wang Zheng-Yu

  第50回日本生物物理学会年会, 2012, English, Domestic conference

  Poster presentation


• 金属及び機能性多糖類によるアントシアニンの耐熱性向上メカニズムの検証

  Tachibana Noriko, Kimura Yukihiro, Ohno Takashi

  日本化学会第92春季年会, 2012, Japanese, Domestic conference

  Poster presentation


• 金属イオンに制御される好熱性紅色光合成細菌由来光捕集反応中心複合体１の色素―蛋白質間相互作用

  Kimura Yukihiro, Inada Yuta, Arikawa Teruhisa, Mumata Tomoko, Yong Li, Wang Zheng-Yu, Ohno Takashi

  日本化学会第92春季年会, 2012, Japanese, Domestic conference

  Oral presentation


• Detection of pigment-protein interactions in photosynthetic purple bacteria by Near Infrared Raman Spectroscopy

  Numata Tomoko, Inada Yuta, Yong Li, Arikawa Teruhisa, Wang Zheng-Yu, Ohno Takashi, Kimura Yukihiro

  Japan Analytical & Scientific Instruments Show, 2012, English, International conference

  Poster 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


• 好熱性紅色細菌Thermochromatium tepidum由来光捕集反応中心複合体の色素—蛋白質間相互作用における金属イオンの役割

  Inada Yuta, Arikawa Teruhisa, Wang Zheng-Yu, Kimura Yukihiro, Ohno Takashi

  第472回日本農芸化関西支部講演会, 2011, Japanese, Domestic conference

  Oral presentation


• 好熱性光合成細菌由来の電子伝達タンパク質の機能評価と構造解析

  Suzuki Hideaki, Hirano Yu, Kimura Yukihiro, Takasaki Masamitsu, Genji Rie, Furusawa Kei, Miki Kunio, Wang Zheng-Yu

  第38回生体分子科学討論会, 2011, Japanese, Domestic conference

  Oral presentation


• Thermochromatium tepidum由来光捕集反応中心複合体における金属結合サイトの特性解析

  Inada Yuta, Kimura Yukihiro, Wang Zheng-Yu, Ohno Takashi

  第19回光合成の色素系と反応中心に関するセミナー, 2011, Japanese, Domestic conference

  Oral presentation


• 生合成的にSr2+置換された好熱性紅色硫黄細菌Thermochromatium tepidumにおける色素蛋白質複合体の特性評価

  Kimura Yukihiro, Inada Yuta, Kasuga Sachiko, Sasaki Yuko, Long-jiang Yu, Wang Zheng-Yu, Ohno Takashi

  第48回日本生物物理学会年会, 2010, English, Domestic conference

  Poster presentation


• 光化学系Ⅱ酸素発生複合体における表在性蛋白質PsbPとカルシウムの構造的、機能的役割

  Yong Li, Kimura Yukihiro, Ohno Takashi

  日本農芸化学会関西支部第467回講演会, 2010, Japanese, Domestic conference

  Oral presentation


• Structural and functional roles of metal cations in the Photosynthetic core complex from thermophilic purple sulfur bacterium Thermochromatium tepidum

  Kimura Yukihiro, Inada Yuta, Hirano Yu, Yu Long-Jiang, Wang Zheng-Yu, Ohno Takashi

  The International Chemical Congress of Pacific Basin Societies, Honolulu, 2010, English, International conference

  Poster presentation


• Strontium Ions Are Functionally Replaceable with Calcium Ions in the Light-Harvesting 1 Reaction Center Core Complex from Thermophilic Purple Sulfur bacterium Thermochromatium tepidum

  Kimura Yukihiro, Inada Yuta, Yu Long-Jiang, Ohno Takashi, Wang Zheng-Yu

  15th International Congress on Photosynthesis, 2010, English, International conference

  Poster presentation


• Interaction between dietary fibers and toxic heavy metals as revealed by vibrational specroscopy

  Ohno Takashi, Tachibana Noriko, Hamada Yukiko, Manabe Siori, Kimura Yukihiro

  The International Chemical Congress of Pacific Basin Societies, Honolulu, 2010, English, International conference

  Poster presentation


• Calcium Ions Are Involved in the Thermostability and the Unusual Red-Shift of LH1 Qy Transition of the Core Complex from Thermophilic Purple Sulfur Bacterium Thermochromatium tepidum

  Kimura Yukihiro, Yu Long-Jiang, Hirano Yu, Suzuki Hiroyuki, Wang Zheng-Yu

  15th International Congress on Photosynthesis, 2010, English, International conference

  Poster presentation


• 好熱性紅色光合成細菌由来Cytochrome c’の耐熱性に関する研究

  Kimura Yukihiro, Hirano Yu, Suzuki Hideaki, Sasaki Yuko, Ohno Takashi, Miki Kunio, Wang Zheng-Yu

  特定領域研究「生体超分子構造」第6回公開シンポジウム, 2009, Japanese, Domestic conference

  Poster presentation


• 好熱性光合成細菌由来のFlavocytochrome cとCytochrome c’の結晶構造解析と機能評価

  Genji Rie, Hirano Yu, Kimura Yukihiro, Kimura Ayano, Miki Kunio, Wang Zheng-Yu

  第9回日本蛋白質科学会年会, 2009, Japanese, Domestic conference

  Poster presentation


• 好熱性光合成細菌Thermochromatium tepudum由来光捕集タンパク質—反応中心複合体の構造解析

  Hirano Yu, Long-jiang Yu, Kimura Yukihiro, Suzuki Hiroaki, Wang Zheng-Yu, Miki Kunio

  特定領域研究「生体超分子構造」第6回公開シンポジウム, 2009, Japanese, Domestic conference

  Poster presentation


• 光合成光捕集反応中心複合体におけるCa2+結合部位の検証

  Kato Shogo, Long-jiang Yu, Hirano Yu, Kimura Yukihiro, Wang Zheng-Yu

  特定領域研究「生体超分子構造」第6回公開シンポジウム, 2009, Japanese, Domestic conference

  Poster presentation


• On the Excitation-Trap Dynamics, Red Absorption and Thermal Stability of the LH1-RC Complex from Photosynthetic Bacterium Thermochromatium tepidum

  Ma Fei, Kimura Yukihiro, Yu Long-Jiang, Wang Peng, Ai Xi-Cheng, Wang Zheng-Yu, Zhang Jian-Ping

  Conference on Lasers and Electro-Optics/Pacific Rim, 2009, English, International conference

  Poster presentation

• American Chemical Society


• JAPAN SOCIETY FOR BIOSCIENCE, BIOTECHNOLOGY, AND AGROCHEMISTRY


• THE BIOPHYSICAL SOCIETY OF JAPAN

• 極限環境光合成微生物における３重耐性化と近赤外光利用の分子戦略

  木村 行宏

  日本学術振興会, 科学研究費助成事業, 基盤研究(C), 神戸大学, Apr. 2022 - Mar. 2025


• Quinone transport mechanisms in the light-harvesting 1 reaction center complexes from phototrophic purple bacteria

  木村 行宏

  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), Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area), Kobe University, Nov. 2020 - Mar. 2022

  本研究では紅色細菌由来のLH1-RC、キノン、脂質を用いて光合成膜を再構成する手法を確立し、様々な組み合わせで再構成した膜について、キノン還元からキノール輸送に至るキノン動態をモニタリングすることにより、膜内部におけるキノン動態の直接的な実験的証拠を得ること、ならびにキノン-タンパク質間相互作用やキノン-脂質間相互作用を検証することにより、キノン-キノール輸送経路およびその分子機構を明らかにすることを目的とした。具体的には、(1) 天然および人工再構成膜調製法の確立、(2) 光合成膜およびLH1-RCにおけるキノール生成の検出、(3) 天然再構成膜、人工再構成膜におけるキノール生成の検出、(4) 再構成膜系キノール生成における同位体置換、キノン置換、脂質置換の効果、(5) ATR-FTIRおよびHPLCを用いた遊離キノールの検出、(6) 形状の異なるLH1-RCを用いた比較研究について検討してきた。 本年度は(3)、(4)の人工再構成膜の系について重点的に研究を進めた。主要構成脂質であるCardiolipin、Phosphatidylglycerol、Phosphatidylethanolamine、Phosphatidylcholineを用いた人工膜の再構成条件を最適化し、光誘起赤外分光法によるキノン・キノール由来の信号検出に成功した。(5)については遊離キノンが検出されなかったことから、LH1-RCのキノン輸送において膜脂質の重要性が示唆された。(6)については、C字型のLH1、キノン輸送関連タンパク質であるPuf XやProtein Uを有するRba. sphaeroidesを用いて測定を行なった結果、キノンの還元に対するC字型リング形状、Puf XやProtein U欠損の効果はほとんど見られなかったが、キノンの拡散輸送に対する効果について現在も検証を進めている。


• 紅色光合成細菌による近赤外光電変換メカニズムの解明

  木村 行宏

  科学研究費補助金／基盤研究(C), Apr. 2019 - Mar. 2022, Principal investigator

  Competitive research funding


• 近赤外光応答性uphill型光合成反応におけるカルシウムイオンの役割

  木村 行宏

  学術研究助成基金助成金／基盤研究(C), Apr. 2016 - Mar. 2019, Principal investigator

  Competitive research funding


• 膜蛋白質耐熱化のメタロミクス研究

  木村 行宏

  科学研究費補助金／基盤研究(C), Apr. 2012 - Mar. 2015, Principal investigator

  Competitive research funding


• Structure analysis and characterization of the LH1-RC complex induced by metal ions

  OTOMO Seiu, MIKI Kunio, KIMURA Yukihiro

  Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (C), Ibaraki University, 2011 - 2013

  The crystal structure of a bacterial photosynthetic light-harvesting-reaction center core complex (LH1-RC) has been determined. The structure reveals a closed arrangement of LH1 complex around the RC, and the LH1 BChl a molecules form a partially overlapping ring with a shorter Mg-Mg spacing compared with that of B850 in LH2. Structural evidence is for first time provided for the possible ubiquinone pathway in the closed LH1 complex. The Ca2+-binding sites are identified. Molecular mechanisms of quinone transport, Ca2+-regulation and interaction between LH1 and RC are described below. The result has been published in Nature.

  Competitive research funding


• Structural and functional roles of Ca2+ in the light-harvesting 1 complex from thermophilic purple sulfur bacterium Thermochromatium tepidum

  KIMURA Yukihiro

  Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Young Scientists (B), Kobe University, 2008 - 2010, Principal investigator

  Ca ions are responsible for unique properties of the purple sulfur photosynthetic bacterium Thermochromatium tepidum which is a moderate thermophile grown at the highest temperature among purple bacteria and shows an unusual LH1 Q_y absorption. The present spectroscopic and thermodynamic analyses revealed that the Ca^<2+>-binding little affects secondary structures of the LH1 proteins but precisely modulates conformation of BChl a and thermal stability of the LH1-RC complex. Furthermore, we discovered that Sr ion is an alternative cofactor biofunctionally replaceable with Ca ion in this thermophilic organism.

  Competitive research funding


• 光合成酸素発生反応機構の解明：マンガンクラスターによる水分解反応の直接検出

  木村 行宏

  日本学術振興会, 科学研究費補助金／若手研究(B), 若手研究(B), 独立行政法人理化学研究所, 2002 - 2003, Principal investigator

  光化学系IIマンガン(Mn)クラスターの配位構造及びMnクラスターが水を酸化して酸素を発生する反応機構を明らかにすることを目的とした。本年度は下記1-3について研究を行った。 1.低波数(650-350cm^<-1>)赤外分光法により同位体標識(^<15>N及び^<13>C)された光化学系IIコア標品(ラン藻Synechocystis sp.PCC6803)の光誘起赤外吸収差スペクトルを測定し、Mhクラスターの骨格振動もしくはMnと酸素配位子間の相互作用に由来するバンドを特定した。また、低波数領域におけるアミノ酸配位子の炭素及び酸素に由来するバンドを特定した。 2.Mnクラスターの推定上の配位子と考えられているD1タンパク質のC末端アラニン(D1-Ala344)を構造的に最も類似性の高いグリシンに変異させることにより、Mnクラスターの骨格構造やアミノ酸配位子の配位構造を反映する振動モードに顕著な変化が見られたことから、C末端アラニンがMnクラスターの配位子であることを強く示唆する結果が得られた。また、複数のカルボキシレートを有する金属キレーターがMnクラスターの配位構造を変形させることを明らかにした。 3.光合成酸素発生反応の4つの状態間遷移に対応する光誘起赤外吸収スペクトル(1700-800cm^<-1>)を測定した。得られたスペクトルに対する^<15>N及び^<13>C同位体置換の効果について分析し、アミノ酸配位子に由来する振動を特定した。この領域ではH_2^<18>O置換の効果が見られなかったため、650-350cm^<-1>の領域について各状態間遷移に対応するH_2^<18>O置換の効果を検証した。その結果、650-600cm^<-1>に全ての状態間遷移において同位体シフトが観測され、これらがMnクラスターによる水分解反応もしくは酸素発生反応に密接に関与するクラスターの骨格構造の変化を反映するものであることが示された。

  Competitive research funding