IUBMB Enzyme Nomenclature


Accepted name: vitamin-K-epoxide reductase (warfarin-insensitive)

Reaction: 3-hydroxy-2-methyl-3-phytyl-2,3-dihydro-1,4-naphthoquinone + oxidized dithiothreitol = 2,3-epoxy-2-methyl-3-phytyl-2,3-dihydro-1,4-naphthoquinone + 1,4-dithiothreitol

Glossary: 2,3-epoxy-2-methyl-3-phytyl-2,3-dihydro-1,4-naphthoquinone = vitamin K 2,3-epoxide

Systematic name: 3-hydroxy-2-methyl-3-phytyl-2,3-dihydronaphthoquinone:oxidized-dithiothreitol oxidoreductase

Comments: Vitamin K 2,3-epoxide is reduced to 3-hydroxy- (and 2-hydroxy-) vitamin K by 1,4-dithiothreitol, which is oxidized to a disulfide. Not inhibited by warfarin [cf. EC, vitamin-K-epoxide reductase (warfarin-sensitive)].

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


1. Mukharji, I. and Silverman, R.B. Purification of a vitamin K epoxide reductase that catalyzes conversion of vitamin K 2,3-epoxide to 3-hydroxy-2-methyl-3-phytyl-2,3-dihydronaphthoquinone. Proc. Natl. Acad. Sci. USA 82 (1985) 2713-2717. [PMID: 3857611]

[EC created 1989 as EC, transferred 2014 to EC]

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