Gamma-glutamyl carboxylase

Gamma-glutamyl carboxylase is an is_associated_with::enzyme that in humans is encoded by the GGCX is_associated_with::gene, located on is_associated_with::chromosome 2 at 2p12.

Function
Gamma-glutamyl carboxylase is an enzyme that catalyzes the is_associated_with::posttranslational modification of is_associated_with::vitamin K-dependent proteins. Many of these vitamin K-dependent proteins are involved in is_associated_with::coagulation so the function of the encoded enzyme is essential for hemostasis. Most is_associated_with::gla domain-containing proteins depend on this carboxylation reaction for is_associated_with::posttranslational modification. In humans, the gamma-glutamyl carboxylase enzyme is most highly expressed in the liver.

Catalytic reaction
Gamma-glutamyl carboxylase oxidizes is_associated_with::Vitamin K hydroquinone to Vitamin K 2,3 epoxide, while simultaneously adding CO2 to protein-bound is_associated_with::glutamic acid (abbreviation = Glu) to form gamma-carboxyglutamic acid (also called gamma-is_associated_with::carboxyglutamate, abbreviation = Gla). The carboxylation reaction will only proceed if the carboxylase enzyme is able to oxidize vitamin K hydroquinone to vitamin K epoxide at the same time; the carboxylation and epoxidation reactions are said to be coupled reactions.

Clinical significance
Mutations in this gene are associated with vitamin K-dependent coagulation defect and PXE-like disorder with multiple coagulation factor deficiency.