IUBMB Enzyme Nomenclature


Accepted name: tetrahydromethanopterin S-methyltransferase

Reaction: 5-methyl-5,6,7,8-tetrahydromethanopterin + CoM + 2 Na+side 1 = 5,6,7,8-tetrahydromethanopterin + 2-(methylsulfanyl)ethane-1-sulfonate + 2 Na+side 2

For diagram of reaction click here.

Glossary: CoM = coenzyme M = 2-sulfanylethane-1-sulfonate
tetrahydromethanopterin = 1-(4-{(1R)-1-[(6S,7S)-2-amino-7-methyl-4-oxo-3,4,5,6,7,8-hexahydropteridin-6-yl]ethylamino}phenyl)-1-deoxy-5-O-{5-O-[(1S)-1,3-dicarboxypropylphosphonato]-α-D-ribofuranosyl}-D-ribitol

Other name(s): tetrahydromethanopterin methyltransferase; mtrA-H (gene names); cmtA (gene name)

Systematic name: 5-methyl-5,6,7,8-tetrahydromethanopterin:2-sulfanylethane-1-sulfonate 2-methyltransferase

Comments: Involved in the formation of methane from CO2 in methanogenic archaea. The reaction involves the export of one or two sodium ions. The enzyme from the archaeon Methanobacterium thermoautotrophicum is a membrane-associated multienzyme complex composed of eight different subunits, and contains a 5'-hydroxybenzimidazolyl-cobamide cofactor, to which the methyl group is attached during the transfer. A soluble enzyme that is induced by the presence of CO has been reported as well [6].

Links to other databases: BRENDA, EAWAG-BBD, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 103406-60-6


1. Sauer, F.D. Tetrahydromethanopterin methyltransferase, a component of the methane synthesizing complex of Methanobacterium thermoautotrophicum. Biochem. Biophys. Res. Commun. 136 (1986) 542-547. [PMID: 3085670]

2. Gartner, P., Ecker, A., Fischer, R., Linder, D., Fuchs, G. and Thauer, R.K. Purification and properties of N5-methyltetrahydromethanopterin:coenzyme M methyltransferase from Methanobacterium thermoautotrophicum. Eur. J. Biochem. 213 (1993) 537-545. [PMID: 8477726]

3. Weiss, D.S., Gartner, P. and Thauer, R.K. The energetics and sodium-ion dependence of N5-methyltetrahydromethanopterin:coenzyme M methyltransferase studied with cob(I)alamin as methyl acceptor and methylcob(III)alamin as methyl donor. Eur. J. Biochem. 226 (1994) 799-809. [PMID: 7813469]

4. Harms, U., Weiss, D.S., Gartner, P., Linder, D. and Thauer, R.K. The energy conserving N5-methyltetrahydromethanopterin:coenzyme M methyltransferase complex from Methanobacterium thermoautotrophicum is composed of eight different subunits. Eur. J. Biochem. 228 (1995) 640-648. [PMID: 7737157]

5. Gottschalk, G. and Thauer, R.K. The Na(+)-translocating methyltransferase complex from methanogenic archaea. Biochim. Biophys. Acta 1505 (2001) 28-36. [PMID: 11248186]

6. Vepachedu, V.R. and Ferry, J.G. Role of the fused corrinoid/methyl transfer protein CmtA during CO-dependent growth of Methanosarcina acetivorans. J. Bacteriol. 194 (2012) 4161-4168. [PMID: 22636775]

[EC created 1989, modified 2000, modified 2017]

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