pfam09472: MtrF (This model is not part of the current CDD release)
Tetrahydromethanopterin S-methyltransferase, F subunit (MtrF)
Many archaea have evolved energy-yielding pathways marked by one-carbon biochemistry featuring novel cofactors and enzymes. This domain is mostly found in MtrF, where it covers the entire length of the protein. This polypeptide is one of eight subunits of the N5-methyltetrahydromethanopterin: coenzyme M methyltransferase complex found in methanogenic archaea. This is a membrane-associated enzyme complex that uses methyl-transfer reactions to drive a sodium-ion pump. MtrF itself is involved in the transfer of the methyl group from N5-methyltetrahydromethanopterin to coenzyme M. Subsequently, methane is produced by two-electron reduction of the methyl moiety in methyl-coenzyme M by another enzyme, methyl-coenzyme M reductase. In some organisms this domain is found at the C terminal region of what appears to be a fusion of the MtrA and MtrF proteins. The function of these proteins is unknown, though it is likely that they are involved in C1 metabolism.