This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Biochemistry
Action of metalloproteinase ? 
Select and explain. 
A. Degradation of collagen, B. Polymerization of collagen, C. Oxidation of collagen, D. Stimulation of collagen
A: Degradation of collagen
Answer: A: Degradation of collagen 
Explanation: Ans. is 'a' i.e., Degradation of collagenDegradation of collagen and other ECM (extracellular matrix) proteins is achieved by matrix metalloproteinases (MMPs).MMPs is a family of enzymes that have in common a 180-residue zinc protease domain.Matrix metalloproteinases include :-Interstitial collagenase (MMP-1, 2, and 3) : Cleave the fibrillar collagen types I, II and III.Gelatinases (MMP-2 and 9) : Degrade amorphous collagen and fibronectin.Stromelysins (MMP-3, 10 and 11) : Act on proteoglycans, laminin, fibronectin and amorphous collagen.Membrane-bound MMPs (ADAMs) : Cleave membrane-bound precursor forms of TNF and TGF-a, releasing the active molecule.