Vitamin K-dependent carboxylase: partial purification of the enzyme by antibody affinity techniques.

The vitamin K-dependent carboxylase activity of bovine liver microsomes has been purified 500-fold by adsorption to an antiprothrombin column and elution with a dodeca peptide which competes with a prothrombin precursor enzyme recognition site. The purified enzyme is devoid of bound precursors, and has the same ratio of vitamin K epoxidase activity to carboxylase activity as the crude microsomal preparation.