IUBMB Enzyme Nomenclature


Accepted name: cobalt-precorrin-6A reductase

Reaction: cobalt-precorrin-6B + NAD+ = cobalt-precorrin-6A + NADH + H+

For diagram of reaction click here.

Other name(s): cbiJ (gene name)

Systematic name: cobalt-precorrin-6B:NAD+ oxidoreductase

Comments: The enzyme, which participates in the anaerobic (early cobalt insertion) pathway of adenosylcobalamin biosynthesis, catalyses the reduction of the double bond between C-18 and C-19 of cobalt-precorrin-6A. The enzyme from the bacterium Bacillus megaterium has no activity with NADPH. See EC, precorrin-6A reductase, for the corresponding enzyme that participates in the aerobic cobalamin biosynthesis pathway.

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


1. Kim, W., Major, T.A. and Whitman, W.B. Role of the precorrin 6-X reductase gene in cobamide biosynthesis in Methanococcus maripaludis. Archaea 1 (2005) 375-384. [PMID: 16243778]

2. 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 2014]

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