IUBMB Enzyme Nomenclature


Accepted name: precorrin-6A reductase

Reaction: precorrin-6B + NADP+ = precorrin-6A + NADPH + H+

For diagram click here.

Other name(s): precorrin-6X reductase; precorrin-6Y:NADP+ oxidoreductase; CobK

Systematic name: precorrin-6B:NADP+ oxidoreductase

Comments: The enzyme, which participates in the aerobic (late cobalt insertion) pathway of adenosylcobalamin biosynthesis, catalyses the reduction of the double bond between C-18 and C-19 of precorrin-6A. See EC, cobalt-precorrin-6A reductase, for the corresponding enzyme that participates in the anaerobic cobalamin biosynthesis pathway.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 137573-72-9


1. Blanche, F., Thibaut, D., Famechon, A., Debussche, L., Cameron, B. and Crouzet, J. Precorrin-6X reductase from Pseudomonas denitrificans: purification and characterization of the enzyme and identification of the structural gene. J. Bacteriol. 174 (1992) 1036-1042. [PMID: 1732193]

2. Warren, M.J., Raux, E., Schubert, H.L. and Escalante-Semerena, J.C. The biosynthesis of adenosylcobalamin (vitamin B12). Nat. Prod. Rep. 19 (2002) 390-412. [PMID: 12195810]

[EC created 1999, modified 2004]

Return to EC 1.3.1 home page
Return to EC 1.3 home page
Return to EC 1 home page
Return to Enzymes home page
Return to IUBMB Biochemical Nomenclature home page