IUBMB Enzyme Nomenclature


Accepted name: [methyl-Co(III) methylamine-specific corrinoid protein]—coenzyme M methyltransferase

Reaction: a [methyl-Co(III) methylamine-specific corrinoid protein] + CoM = methyl-CoM + a [Co(I) methylamine-specific corrinoid protein]

Glossary: CoM = coenzyme M = 2-sulfanylethane-1-sulfonate = 2-mercaptoethanesulfonate (deprecated)

Other name(s): methyltransferase 2 (ambiguous); MT2 (ambiguous); MT2-A; mtbA (gene name)

Systematic name: methylated monomethylamine-specific corrinoid protein:Coenzyme M methyltransferase

Comments: Contains zinc [2]. The enzyme, which is involved in methanogenesis from mono-, di-, and trimethylamine, catalyses the transfer of a methyl group bound to the cobalt cofactor of several corrinoid proteins (mono-, di-, and trimethylamine-specific corrinoid proteins (cf. EC, methylamine—corrinoid protein Co-methyltransferase, EC, dimethylamine—corrinoid protein Co-methyltransferase, and EC, trimethylamine—corrinoid protein Co-methyltransferase) to coenzyme M, forming the substrate for EC, coenzyme-B sulfoethylthiotransferase, the enzyme that catalyses the final step in methanogenesis.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:


1. Burke, S.A. and Krzycki, J.A. Involvement of the "A" isozyme of methyltransferase II and the 29-kilodalton corrinoid protein in methanogenesis from monomethylamine. J. Bacteriol. 177 (1995) 4410-4416. [PMID: 7635826]

2. LeClerc, G.M. and Grahame, D.A. Methylcobamide:coenzyme M methyltransferase isozymes from Methanosarcina barkeri. Physicochemical characterization, cloning, sequence analysis, and heterologous gene expression. J. Biol. Chem. 271 (1996) 18725-18731. [PMID: 8702528]

3. Ferguson, D.J., Jr. and Krzycki, J.A. Reconstitution of trimethylamine-dependent coenzyme M methylation with the trimethylamine corrinoid protein and the isozymes of methyltransferase II from Methanosarcina barkeri. J. Bacteriol. 179 (1997) 846-852. [PMID: 9006042]

4. Burke, S.A., Lo, S.L. and Krzycki, J.A. Clustered genes encoding the methyltransferases of methanogenesis from monomethylamine. J. Bacteriol. 180 (1998) 3432-3440. [PMID: 9642198]

5. Ferguson, D.J., Jr., Gorlatova, N., Grahame, D.A. and Krzycki, J.A. Reconstitution of dimethylamine:coenzyme M methyl transfer with a discrete corrinoid protein and two methyltransferases purified from Methanosarcina barkeri. J. Biol. Chem. 275 (2000) 29053-29060. [PMID: 10852929]

[EC created 2012]

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