Vitamin K2 is a vitamin which is usually present in bacterial fermented foods. It serves as a cofactor for the enzyme gamma-glutamyl carboxylase, which performs the gamma carboxylation of several proteins.
One of this proteins is called matrix gla protein (MGP). This protein inhibits the calcification in cartilage and vascular tissue. In order for this protein to perform well inhibiting calcification, it has to be adequately gamma carboxylated.
If there is deficiency of vitamin K2, there may be increased calcification of vascular and cartilage tissue.
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