This non-hemorrhagic metalloprotease hydrolyzes the Aalpha chain of fibrin and fibrinogen first followed by the Bbeta chain and shows no effect on the gamma chain. It is also able to degrade type I collagen, fibronectin, laminin and induces inflammatory reaction. It is devoid of hemorrhagic and thrombotic activities, but induces pulmonary bleeding. It also induces a mild myotoxic reaction. It is not able to inhibit platelet aggregation, but it induces decrease of platelets and plasma fibrinogen. It contributes to local tissue damage by inducing edema, inflammatory infiltrate and mild myotoxicity, and by degrading extracellular matrix components. Cleaves insulin B chain at '38-Ala-|-Leu-39' and '40-Tyr-|-Leu-41' bonds (PubMed:11032408). Binds 1 zinc ion per subunit. Inhibited by EDTA, EGTA and 1,10-phenanthroline, partially inhibited by beta-mercaptoethanol and not inhibited by serine protease inhibitors (leupeptin and aprotinin). Also inhibited by an excess of zinc, mercury and magnesium ions. Extracts of the plant Casearia mariquitensis neutralizes the decrease of platelets and plasma fibrinogen induced by the protease. The same extracts also partially inhibit Bbeta chain cleavage, but not Aalpha chain cleavage. Optimum pH is 7.4-8.0. Optimum temperature is 37 degrees Celsius. Monomer. Expressed by the venom gland. LD(50) is 5 mg/kg by intravenous injection into mice. Belongs to the venom metalloproteinase (M12B) family. P-I subfamily.