Tetrahydromethanopterin S-methyltransferase, subunit H/Methyltransferase Mtx, subunit H (IPR023467)

Short name: MeTrfase_MtrH/MtxH

Overlapping homologous superfamilies

Family relationships


In archaea the enzyme tetrahydromethanopterin S-methyltransferase is composed of eight subunits, MtrA-H. The enzyme is a membrane- associated enzyme complex which catalyzes an energy-conserving, sodium-ion-translocating step in methanogenesis from hydrogen and carbon dioxide [PMID: 7737157]. Subunit MtrH catalyzes the methylation reaction and was shown to exhibit methyltetrahydromethanopterin:cob(I)alamin methyltransferase activity [PMID: 10338124].

CH3-H4MPT + cob(I)alamin --> H4MPT + CH3-cob(III)alamin (H4MPT = tetrahydromethanopterin)

Methyltransferase MtxH from the archaea Methanosarcina may be part of a complex composed of 3 subunits; MtxA, MtxH and MtxX [PMID: 9461302].

This entry also includes methylcorrinoid:tetrahydrofolate methyltransferase from Desulfitobacterium hafniense, which in vitro catalyses the transfer of a methyl group from methylcobalamin to tetrahydrofolate. In vivo this may permit anaerobic methylotrophic growth using glycine betaine [PMID: 25313086].

GO terms

Biological Process

GO:0006730 one-carbon metabolic process

Molecular Function

GO:0008168 methyltransferase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.