Hokkaido University Collection of Scholarly and Academic Papers >
Institute of Low Temperature Science >
Peer-reviewed Journal Articles, etc >
Spectroscopic and biochemical insight into an electron-bifurcating [FeFe] hydrogenase
This item is licensed under:Creative Commons Attribution 4.0 International
Title: | Spectroscopic and biochemical insight into an electron-bifurcating [FeFe] hydrogenase |
Authors: | Chongdar, Nipa Browse this author | Pawlak, Krzysztof Browse this author | Ruediger, Olaf Browse this author | Reijerse, Edward J. Browse this author | Rodriguez-Macia, Patricia Browse this author | Lubitz, Wolfgang Browse this author | Birrell, James A. Browse this author | Ogata, Hideaki Browse this author →KAKEN DB |
Keywords: | [FeFe] hydrogenase | Electron bifurcation | Spectroscopy | Electrochemistry | Ferredoxin |
Issue Date: | Feb-2020 |
Publisher: | Springer |
Journal Title: | Journal of Biological Inorganic Chemistry |
Volume: | 25 |
Issue: | 1 |
Start Page: | 135 |
End Page: | 149 |
Publisher DOI: | 10.1007/s00775-019-01747-1 |
Abstract: | The heterotrimeric electron-bifurcating [FeFe] hydrogenase (HydABC) from Thermotoga maritima (Tm) couples the endergonic reduction of protons (H+) by dihydronicotinamide adenine dinucleotide (NADH) ( increment G(0) approximate to 18 kJ mol(-1)) to the exergonic reduction of H+ by reduced ferredoxin (Fd(red)) ( increment G(0) approximate to - 16 kJ mol(-1)). The specific mechanism by which HydABC functions is not understood. In the current study, we describe the biochemical and spectroscopic characterization of TmHydABC recombinantly produced in Escherichia coli and artificially maturated with a synthetic diiron cofactor. We found that TmHydABC catalyzed the hydrogen (H-2)-dependent reduction of nicotinamide adenine dinucleotide (NAD(+)) in the presence of oxidized ferredoxin (Fd(ox)) at a rate of approximate to 17 mu mol NADH min(-1) mg(-1). Our data suggest that only one flavin is present in the enzyme and is not likely to be the site of electron bifurcation. FTIR and EPR spectroscopy, as well as FTIR spectroelectrochemistry, demonstrated that the active site for H-2 conversion, the H-cluster, in TmHydABC behaves essentially the same as in prototypical [FeFe] hydrogenases, and is most likely also not the site of electron bifurcation. The implications of these results are discussed with respect to the current hypotheses on the electron bifurcation mechanism of [FeFe] hydrogenases. Overall, the results provide insight into the electron-bifurcating mechanism and present a well-defined system for further investigations of this fascinating class of [FeFe] hydrogenases. Graphic abstract |
Rights: | http://creativecommons.org/licenses/by/4.0 |
Type: | article |
URI: | http://hdl.handle.net/2115/77971 |
Appears in Collections: | 低温科学研究所 (Institute of Low Temperature Science) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)
|
Submitter: 緒方 英明
|