Which coagulation factors require vitamin K for gamma-carboxylation of their glutamic acid residues?

• A Factors II, V, VII, X
• B Factors VIII, IX, XI, XII
• C Factors I, V, VIII, XIII
• D Factors II, VII, IX, X ✓

Explanation

Vitamin K is a cofactor for gamma-glutamyl carboxylase, which converts glutamic acid residues to gamma-carboxyglutamic acid in factors II, VII, IX, X and the regulatory proteins C and S. This modification allows calcium-dependent binding to phospholipid surfaces. Factors V and VIII are glycoproteins that do not undergo vitamin K-dependent carboxylation, which eliminates options C and A.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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