<prompt> Which is Vitamin K dependent clotting factor?Factor VIIFactor IFactor XIFactor XII  <response>: Ans is a i.e. Factor VII Vitamin K serves as an essential cofactor for an enzyme carboxylase that catalyzes carboxylation of glutamic acid residues on vitamin K-dependent proteins. The key vitamin K-dependent proteins include:Coagulation proteins: factors II prothrombin, VII, IX and XAnticoagulation proteins: proteins C, S and ZOthers: bone proteins osteocalcin and matrix-Gla protein, and certain ribosomal proteinsThese proteins have in common the requirement to be post-translationally modified by carboxylation of glutamic acid residues forming gamma-carboxyglutamic acid in order to become biologically active. 