title: Characterization of Ac3-proteinase from the venom of Agkistrodon acutus (hundred-pace snake).
abstract: Ac3-Proteinase from the venom of Agkistrodon acutus was isolated in a homogeneous form by a previously published method. Ac3-Proteinase possessed lethal, hemorrhagic, caseinolytic, azocaseinolytic, dimethylcaseinolytic and hide powder azure hydrolytic activities. These activities were inhibited when Ac3-Proteinase was incubated with the metal chelators ethylenediaminetetraacetic acid (EDTA), ethyleneglycol-bis-(beta-aminoethyl ether)-N,N'-tetraacetic acid (EGTA), tetraethylenepentamine (TEP), 1,10-phenanthroline, phosphoramidon or beta-mercaptoethanol. The toxin also hydrolyzed the oxidized A and B chains of both insulin and fibrinogen. The cleavage sites in the oxidized B chain of insulin were identified as His(10)-Leu(11), Ala(14)-Leu(15), Tyr(16)-Leu(17) and Phe(24)-Phe(25). The A alpha chain of fibrinogen was digested first followed by hydrolysis of the B beta chain. Toxicological and biochemical properties of Ac3-Proteinase were investigated further and are reported in this paper.
mesh_terms: D000803:Angiotensin I; D000818:Animals; D002364:Caseins; D003402:Creatine Kinase / Q000378:metabolism; D003435:Crotalid Venoms / Q000032:analysis*; D010450:Endopeptidases / Q000302:isolation & purification* / Q000378:metabolism / Q000633:toxicity; D006470:Hemorrhage / Q000139:chemically induced; D051379:Mice; D009336:Necrosis; D010455:Peptides; D013379:Substrate Specificity; D013917:Thrombin / Q000378:metabolism
chemical_list: D002364:Caseins; D003435:Crotalid Venoms; D010455:Peptides; D000803:Angiotensin I; D003402:Creatine Kinase; D010450:Endopeptidases; D013917:Thrombin; C043228:Ac3-proteinase