IUBMB Enzyme Nomenclature


Accepted name: cobalt-precorrin-5B (C1)-methyltransferase

Reaction: cobalt-precorrin-5B + S-adenosyl-L-methionine = cobalt-precorrin-6A + S-adenosyl-L-homocysteine

For diagram click here.

Glossary: cobalt-precorrin-6A = cobalt-precorrin-6x

Other name(s): cobalt-precorrin-6A synthase; CbiD (gene name)

Systematic name: S-adenosyl-L-methionine:cobalt-precorrin-5B (C1)-methyltransferase

Comments: This enzyme catalyses the C-1 methylation of cobalt-precorrin-5B in the anaerobic (early cobalt insertion) pathway of adenosylcobalamin biosynthesis.

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


1. Roper, J.M., Raux, E., Brindley, A.A., Schubert, H.L., Gharbia, S.E., Shah, H.N. and Warren, M.J. The enigma of cobalamin (Vitamin B12) biosynthesis in Porphyromonas gingivalis. Identification and characterization of a functional corrin pathway. J. Biol. Chem. 275 (2000) 40316-40323. [PMID: 11007789]

2. Roessner, C.A., Williams, H.J. and Scott, A.I. Genetically engineered production of 1-desmethylcobyrinic acid, 1-desmethylcobyrinic acid a,c-diamide, and cobyrinic acid a,c-diamide in Escherichia coli implies a role for CbiD in C-1 methylation in the anaerobic pathway to cobalamin. J. Biol. Chem. 280 (2005) 16748-16753. [PMID: 15741157]

3. Moore, S.J., Lawrence, A.D., Biedendieck, R., Deery, E., Frank, S., Howard, M.J., Rigby, S.E. and Warren, M.J. Elucidation of the anaerobic pathway for the corrin component of cobalamin (vitamin B12). Proc. Natl. Acad. Sci. USA 110 (2013) 14906-14911. [PMID: 23922391]

[EC created 2010]

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