Vitamin-K-epoxide reductase (warfarin-sensitive) explained

vitamin-K-epoxide reductase (warfarin-sensitive)
Ec Number:	1.17.4.4
Cas Number:	55963-40-1
Go Code:	0047057

In enzymology, a vitamin-K-epoxide reductase (warfarin-sensitive) is an enzyme that catalyzes the chemical reaction

2-methyl-3-phytyl-1,4-naphthoquinone + oxidized dithiothreitol

\rightleftharpoons 2,3-epoxy-2,3-dihydro-2-methyl-3-phytyl-1,4-naphthoquinone + 1,4-dithiothreitol

Thus, the two substrates of this enzyme are 2-methyl-3-phytyl-1,4-naphthoquinone and oxidized dithiothreitol, whereas its two products are 2,3-epoxy-2,3-dihydro-2-methyl-3-phytyl-1,4-naphthoquinone and 1,4-dithiothreitol.

This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH or CH2 groups of donor with a disulfide as acceptor. The systematic name of this enzyme class is 2-methyl-3-phytyl-1,4-naphthoquinone:oxidized-dithiothreitol oxidoreductase. This enzyme participates in biosynthesis of steroids. At least one compound, Warfarin is known to inhibit this enzyme.

References

• Lee JJ, Fasco MJ . 1984 . Metabolism of vitamin K and vitamin K 2,3-epoxide via interaction with a common disulfide . Biochemistry . 23 . 2246–52 . 6733086 . 10.1021/bi00305a024 . 10 .
• Mukharji I, Silverman RB . 1985 . 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. U.S.A. . 82 . 2713–7 . 3857611 . 10.1073/pnas.82.9.2713 . 9 . 397635 . free . 1985PNAS...82.2713M .
• Whitlon DS, Sadowski JA, Suttie JW . 1978 . Mechanism of coumarin action: significance of vitamin K epoxide reductase inhibition . Biochemistry . 17 . 1371–7 . 646989 . 10.1021/bi00601a003 . 8 .