期刊
SCIENCE
卷 373, 期 6559, 页码 1151-1155出版社
AMER ASSOC ADVANCEMENT SCIENCE
DOI: 10.1126/science.abg5550
关键词
-
资金
- Max Planck Society
- Deutsche Forschungsgemeinschaft [SH 87/1-1]
- Alexander von Humboldt Foundation
- Japan Society for the Promotion of Science
The study reports enzymological and structural characteristics of the CO2 reduction reaction in the methanogenic pathway, revealing the mechanism of the complex using formate and F-420 electron reduction form. Conformational changes in HdrA mediate electron bifurcation, while FmdF directly transfers electrons to the CO2 reduction site, confirming the ubiquity of this complex.
The first reaction of the methanogenic pathway from carbon dioxide (CO2) is the reduction and condensation of CO2 to formyl-methanofuran, catalyzed by formyl-methanofuran dehydrogenase (Fmd). Strongly reducing electrons for this reaction are generated by heterodisulfide reductase (Hdr) in complex with hydrogenase or formate dehydrogenase (Fdh) using a flavin-based electron-bifurcation mechanism. Here, we report enzymological and structural characterizations of Fdh-Hdr-Fmd complexes from Methanospirillum hungatei. The complexes catalyze this reaction using electrons from formate and the reduced form of the electron carrier F-420. Conformational changes in HdrA mediate electron bifurcation, and polyferredoxin FmdF directly transfers electrons to the CO2 reduction site, as evidenced by methanofuran-dependent flavin-based electron bifurcation even without free ferredoxin, a diffusible electron carrier between Hdr and Fmd. Conservation of Hdr and Fmd structures suggests that this complex is common among hydrogenotrophic methanogens.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据