Protein
Methyl-coenzyme M reductase I subunit gamma
Organism
Methanothermobacter marburgensis (strain ATCC BAA-927 / DSM 2133 / JCM 14651 / NBRC 100331 / OCM 82 / Marburg)
Function
Component of the methyl-coenzyme M reductase (MCR) I that catalyzes the reductive cleavage of methyl-coenzyme M (CoM-S-CH3 or 2-(methylthio)ethanesulfonate) using coenzyme B (CoB or 7-mercaptoheptanoylthreonine phosphate) as reductant which results in the production of methane and the mixed heterodisulfide of CoB and CoM (CoM-S-S-CoB). This is the final step in methanogenesis (PubMed:2269306, PubMed:3350018). Neither N-6-mercaptohexanoylthreonine phosphate (H-S-HxoTP) nor N-8-mercaptooctanoylthreonine phosphate (H-SOcoTP) nor any other thiol compound such as CoA or CoM can substitute for CoB as the electron donor (PubMed:3350018).
Similarity
Belongs to the methyl-coenzyme M reductase gamma subunit family.
Sequence
MAQYYPGTTKVAQNRRNFCNPEYELEKLREISDEDVVKILGHRAPGEEYPSVHPPLEEMDEPEDAIREMVEPIDGAKAGDRVRYIQFTDSMYFAPAQPYVRSRAYLCRYRGADAGTLSGRQIIETRERDLEKISKELLETEFFDPARSGVRGKSVHGHSLRLDEDGMMFDMLRRQIYNKDTGRVEMVKNQIGDELDEPVDLGEPLDEETLMEKTTIYRVDGEAYRDDVEAVEIMQRIHVLRSQGGFNLE