Structural highlights
Function
Q2FKZ1_METHJ Part of a complex that catalyzes the reversible reduction of CoM-S-S-CoB to the thiol-coenzymes H-S-CoM (coenzyme M) and H-S-CoB (coenzyme B).[RuleBase:RU366072]
Publication Abstract from PubMed
The first reaction of the methanogenic pathway from carbon dioxide (CO(2)) is the reduction and condensation of CO(2) 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 CO(2) 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.
Three-megadalton complex of methanogenic electron-bifurcating and CO(2)-fixing enzymes.,Watanabe T, Pfeil-Gardiner O, Kahnt J, Koch J, Shima S, Murphy BJ Science. 2021 Sep 3;373(6559):1151-1156. doi: 10.1126/science.abg5550. Epub 2021 , Sep 1. PMID:34516836[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Watanabe T, Pfeil-Gardiner O, Kahnt J, Koch J, Shima S, Murphy BJ. Three-megadalton complex of methanogenic electron-bifurcating and CO(2)-fixing enzymes. Science. 2021 Sep 3;373(6559):1151-1156. PMID:34516836 doi:10.1126/science.abg5550
