vitamin-K-epoxide reductase (warfarin-insensitive) activity
Definition
Target type: molecularfunction
Catalysis of the reaction: 3-hydroxy-2-methyl-3-phytyl-2,3-dihydronaphthoquinone + oxidized dithiothreitol + H2O = 2,3-epoxy-2,3-dihydro-2-methyl-3-phytyl-1,4-naphthoquinone + 1,4-dithiothreitol. [RHEA:21560]
Vitamin-K-epoxide reductase (warfarin-insensitive) activity is a crucial enzyme involved in the post-translational modification of proteins essential for blood coagulation. Specifically, it catalyzes the reduction of vitamin K epoxide (the inactive form of vitamin K) back to vitamin K hydroquinone, which is the active cofactor for the γ-carboxylation of glutamate residues in several coagulation factors. This process is essential for the activation of these factors, which then participate in the coagulation cascade leading to the formation of a stable blood clot. The enzyme's warfarin-insensitive nature signifies its resistance to inhibition by the anticoagulant drug warfarin, which works by blocking the activity of the classical vitamin K epoxide reductase (VKORC1). This makes the warfarin-insensitive reductase an important target for investigating alternative anticoagulant strategies. It plays a key role in maintaining hemostasis, the process of blood clotting, by ensuring a sufficient supply of the active vitamin K cofactor for the proper functioning of coagulation factors. The enzyme is crucial for regulating blood clotting and preventing excessive bleeding.'
"
Proteins (1)
| Protein | Definition | Taxonomy |
|---|---|---|
| Vitamin K epoxide reductase complex subunit 1 | A vitamin K epoxide reductase complex subunit 1 that is encoded in the genome of human. [PRO:DNx, UniProtKB:Q9BQB6] | Homo sapiens (human) |
Compounds (1)
| Compound | Definition | Classes | Roles |
|---|---|---|---|
| warfarin | 4-hydroxy-3-(3-oxo-1-phenylbutyl)-1-benzopyran-2-one : A member of the class of coumarins that is 4-hydroxycoumarin which is substituted at position 3 by a 1-phenyl-3-oxo-1-butyl group. warfarin : A racemate comprising equal amounts of (R)- and (S)-warfarin. Extensively used as both an anticoagulant drug and as a pesticide against rats and mice. Warfarin: An anticoagulant that acts by inhibiting the synthesis of vitamin K-dependent coagulation factors. Warfarin is indicated for the prophylaxis and/or treatment of venous thrombosis and its extension, pulmonary embolism, and atrial fibrillation with embolization. It is also used as an adjunct in the prophylaxis of systemic embolism after myocardial infarction. Warfarin is also used as a rodenticide. | benzenes; hydroxycoumarin; methyl ketone |