2015 Fiscal Year Final Research Report
Structural chemistry of O2-tolerant [NiFe]-hydrogenases
Project/Area Number |
25291038
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Research Category |
Grant-in-Aid for Scientific Research (B)
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Allocation Type | Partial Multi-year Fund |
Section | 一般 |
Research Field |
Biophysics
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Research Institution | University of Hyogo |
Principal Investigator |
Higuchi Yoshiki 兵庫県立大学, 生命理学研究科, 教授 (90183574)
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Project Period (FY) |
2013-04-01 – 2016-03-31
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Keywords | X線結晶解析 / 酸素耐性酵素 / Ni酵素 / ヒドロゲナーゼ / 燃料電池 / 中性子結晶解析 / 反応機構 / プロトンチャネル |
Outline of Final Research Achievements |
In this study, x-ray structure analysis of newly found O2-tolerant [NiFe]-hydrogenase and neutron structure analysis of standard enzyme have been carried out. 1. The x-ray structures of the newly found O2-tolerant [NiFe]-hydrogenase from Citrobacter sp. S-77 in the air-oxidized, K3Fe(CN)6-oxidized and H2-reduced forms have been successfully solved at the resolutions better than 2.0 A. The one of the iron-sulfur clusters (the proximal to the Ni-Fe active site) is not a [4Fe3S]-type, which was found in the usual O2-tolerant enzymes, but a [4Fe4S]-type typical as those in the standard enzymes. This [4Fe4S]-type cluster changed its structure when the enzyme is oxidized by K3Fe(CN)6, but the mechanism of the structural changed are different from those clusters in O2-tolerant hydrogenase. 2. Neutron diffraction data up to 2.0 A resolution have been successfully obtained from a large crystal (>1.5 mm3) grown in D2O.
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Free Research Field |
構造生物学
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