Hemorrhagic metalloproteinase, Cc HSM-III, isolated from Cerastes cerastes venom: Purification and biochemical characterization.

Snake venom metalloproteinases are the most abundant toxins in Viperidae venoms. In this study, a new hemorrhagin, Cc HSM-III (66 kDa), was purified from Cerastes cerastes venom by gel filtration, ion exchange, and reversed-phase high-performance liquid chromatographies. The analysis of Cc HSM-III by liquid chromatography with a tandem mass spectrometry revealed 32 peptides sharing a homology with P-III metalloproteinases from Echis ocellatus snake venom. Cc HSM-III displays hemorrhagic activity with a minimal hemorrhagic dose of 5 μg, which is abolished by ethylene diamine tetracetic acid but not by phenylmethylsulfonyl fluoride. The mechanism underlying Cc HSM-III hemorrhagic activity is probably due to its extensive proteolytic activity against type IV collagen. Cc HSM-III induces local tissue damage and an inflammatory response by upregulating both matrix metalloproteinase 2 and 9 in skin of mice. Thus, Cc HSM-III may play a key role in the pathogenesis of C. cerastes envenomation.