Vitamin K epoxide reductase (VKOR) recycles vitamin K 2,3-epoxide to vitamin K hydroquinone, a co-factor that is essential for the posttranslational γ-carboxylation of several blood coagulation factors [ PUBMED:14765194 ]. VKORC1, the catalytic subunit of the VKOR complex, is a member of a large family of predicted enzymes … expand

Vitamin K epoxide reductase (VKOR) recycles vitamin K 2,3-epoxide to vitamin K hydroquinone, a co-factor that is essential for the posttranslational γ-carboxylation of several blood coagulation factors [ PUBMED:14765194 ]. VKORC1, the catalytic subunit of the VKOR complex, is a member of a large family of predicted enzymes that are present in vertebrates, Drosophila, plants, bacteria and archaea [ PUBMED:15276181 PUBMED:24477003 ]. Bacterial VKOR homologues catalyse disulphide bridge formation in secreted proteins by cooperating with a periplasmic, Trx-like redox partner [ PUBMED:18413314 PUBMED:18695247 ]. In fact, in some plant and bacterial homologues the VKORC1 homologous domain is fused with domains of the thioredoxin family of oxidoreductases [ PUBMED:15276181 ]. VKOR is part of a disulphide bond formation pathway that uses electrons from cysteines of newly synthesized proteins to reduce a quinone [ PUBMED:20110994 ].