title: Isolation and characterization of a toxic phospholipase A2 from the venom of the Taiwan habu (Trimeresurus mucrosquamatus).
abstract: A toxic phospholipase A2 (PLA2) was isolated from Taiwan-habu-snake (Trimeresurus mucrosquamatus) venom by sequential chromatographies on CM-52, Sephadex G-75 and S-Sepharose columns. This basic PLA2 has a single polypeptide with an estimated M(r) of 15,000. The PLA2 activity was Ca(2+)-dependent and inactivated by p-bromophenacyl bromide and its specific antibody. The toxic PLA2-induced myotoxic and direct haemolytic effects as well as respiratory distress in mice with an intraperitoneal LD50 of 1.17 micrograms/g body weight. The histological examination showed it caused haemorrhage and congestion in the viscera of mice. It was also cytotoxic to myeloma cells (NS-1), baby-hamster-kidney (BHK) cells and human umbilical endothelial cells. By neutralization experiments with a specific antibody against toxic PLA2, it was found that the enzymic activity of toxic PLA2 is essential for its myotoxicity, but it is not the only factor responsible for the lethal toxicity.
authors.affiliation: Department of Biochemistry, Kaohsiung Medical College, Taiwan, Republic of China.
authors.forename: L N
authors.initials: LN
authors.lastname: Chen
authors.forename: C S
authors.initials: CS
authors.lastname: Liu
authors.forename: C C
authors.initials: CC
authors.lastname: Chang
mesh_terms: D000098:Acetophenones / Q000494:pharmacology; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002118:Calcium / Q000494:pharmacology; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D002852:Chromatography, Ion Exchange; D006224:Cricetinae; D003435:Crotalid Venoms / Q000201:enzymology*; D006321:Heart / Q000187:drug effects; D006461:Hemolysis; D006470:Hemorrhage / Q000139:chemically induced; D006801:Humans; D007668:Kidney / Q000187:drug effects; D008168:Lung / Q000187:drug effects / Q000473:pathology; D008297:Male; D051379:Mice; D008970:Molecular Weight; D009206:Myocardium / Q000473:pathology; D010741:Phospholipases A / Q000737:chemistry / Q000302:isolation & purification* / Q000633:toxicity*; D054467:Phospholipases A2; D014407:Tumor Cells, Cultured
chemical_list: D000098:Acetophenones; D000596:Amino Acids; D003435:Crotalid Venoms; C029748:Trimeresurus venoms; D010741:Phospholipases A; D054467:Phospholipases A2; C006821:4-bromophenacyl bromide; D002118:Calcium