by
bahjat alabou houseen , clinical hematologist , KING ABDULAZIZ SPECIALIZED HOSPITAL IN TAIF
Vit K is essential for activity of several carboxylase enzymes within the hepatic cells,and therefore is necessary for the activation of coagulation factors VII,IX,X,II.These factors contain carboxyglutamic acid,which is carboxylated by gamma-glutamyl carboxylase. Vit K is the active coenzyme in this process,providing energy for the reaction through oxidation,after carboxylation,these proteins gain affinity for the negatively charged phospholipids on the surface of platelets and promote coagulation.