1. Hepatic and peripheral carboxylation of VKDPs
Hepatic and peripheral carboxylation of VKDPs. Vitamin K-dependent proteins undergo carboxylation to become biologically active, requiring vitamin K as a cofactor in the conversion.
Hepatic and peripheral carboxylation of VKDPs. Vitamin K-dependent proteins undergo carboxylation to become biologically active, requiring vitamin K as a cofactor in the conversion. In hepatic carboxylation, the liver uses vitamin K1 to activate the coagulation factors. In a distinct process, vascular smooth muscle cells produce and activate MGP and Gas-6, two proteins with important roles in vascular biology, affecting cell movement, survival, and calcification. This peripheral carboxylation primarily depends on a family of menaquinones, collectively known as vitamin K2, which differ in structure and metabolism from vitamin K1. Vitamin K1 predominantly is derived from the diet. Vitamin K2 comes either from enterocyte conversion of vitamin K1 or from indigenous intestinal bacteria production.
John Danziger CJASN 2008;3:
©2008 by American Society of Nephrology