Vit K is needed for which of these posttranslational modification processes: (A) Methylation, (B) Carboxylation, (C) Hydroxylation, (D) Transketolation
Answer is B. Vitamin K functions as a cofactor for an enzyme carboxylase that catalyzes post-translation modification by carboxylation of glutamic acid (glutamate) residues on vitamin K dependent proteins.