Vitamin K-dependent protein (VKDP) (VKDP)

Vitamin K-dependent proteins (VKDPs), also referred to as gamma-glutamyl carboxylase-dependent proteins, are a specialized group of proteins that require post-translational modification to become biologically functional. This modification is performed by the enzyme gamma-glutamyl carboxylase (GGCX), which converts specific glutamic acid residues into gamma-carboxyglutamic acid (Gla) residues using reduced vitamin K as an essential cofactor [1, 2]. The resulting Gla residues enable these proteins to bind calcium ions, a process critical for their association with phospholipid membranes or the bone matrix [3]. This group includes essential coagulation factors such as Prothrombin (Factor II), Factor VII, Factor IX, and Factor X, as well as anticoagulant proteins C and S [2]. Additionally, VKDPs like Matrix Gla protein (MGP) and Osteocalcin play vital roles in regulating bone mineralization and preventing the calcification of blood vessels [4, 5]. Pharmacologically, these proteins are the primary downstream effectors of vitamin K antagonists like warfarin, which inhibit their activation to prevent thromboembolic events, and are also the direct targets of modern anticoagulants like rivaroxaban and dabigatran [1, 3].

Other names

Gamma-glutamyl carboxylase-dependent proteinGla proteinVitamin K-dependent coagulation factorVKDP

Inhibition of the vitamin K cycle prevents the gamma-carboxylation of these proteins, rendering them inactive; alternatively, direct oral anticoagulants (DOACs) specifically inhibit the activated forms of individual proteins within this group.