Cob(II)yrinic acid a,c-diamide reductase

In enzymology, a cob(II)yrinic acid a,c-diamide reductase () is an enzyme that catalyzes the chemical reaction
2 cob(I)yrinic acid a,c-diamide + FMN + 3 H+ formula_1 2 cob(II)yrinic acid a,c-diamide + FMNH2
The three substrates of this enzyme are cob(I)yrinic acid a,c-diamide, flavin mononucleotide, and H+; its two products are cob(II)yrinic acid a,c-diamide and FMNH2.
Classification.
This enzyme belongs to the family of oxidoreductases, specifically those oxidizing metal ion with a flavin as acceptor.
Nomenclature.
The systematic name of this enzyme class is cob(I)yrinic acid-a,c-diamide:FMN oxidoreductase. This enzyme is also called CobR and cob(II)yrinic acid-a,c-diamide:FMN oxidoreductase (incorrect).
Biological role.
This enzyme is part of the biosynthetic pathway to cobalamin (vitamin B12) in bacteria. 