Characterization and cloning of a novel phospholipase A(2) from the venom of Trimeresurus jerdonii snake.
A phospholipase A(2) (PLA(2)), called jerdoxin, was isolated from Trimeresurus jerdonni snake venom and partially characterized. The protein was purified by three chromatographic steps. SDS-polyacrylamide gel electrophoresis in the presence or absence of dithiothreitol showed that it had a molecular mass of 15 kDa. Jerdoxin had an enzymatic activity of 39.4 micro mol/min/mg towards egg yolk phosphatidyl choline (PC). It induced edema in the footpads of mice. In addition, jerdoxin exhibited indirect hemolytic activity. About 97% hemolysis was observed when 2 micro g/ml enzyme was incubated for 90 min in the presence of PC and Ca(2+). No detectable hemolysis was noticed when PC was not added. Ca(2+) was necessary for jerdoxin to exert its hemolytic activity, since only 52% hemolysis was seen when Ca(2+) was absent in the reaction mixture. Furthermore, jerdoxin inhibited ADP induced rabbit platelet aggregation and the inhibition was dose dependent with an IC(50) of 1.0 micro M. The complete amino acid sequence of jerdoxin deduced from cDNA sequence shared high homology with other snake venom PLA(2)s, especially the D 49 PLA(2)s. Also, the residues concerned to Ca(2+) binding were conserved. This is the first report of cDNA sequence of T. jerdonii venom PLA(2).
Lu
Qiu-Min
QM
Department of Animal Toxicology, Kunming Institute of Zoology, Chinese Academy of Sciences, 650223, Yunnan, Kunming, People's Republic of China.
Jin
Yang
Y
Wei
Ji-Fu
JF
Li
Dong-Sheng
DS
Zhu
Shao-Wen
SW
Wang
Wan-Yu
WY
Xiong
Yu-Liang
YL
D000595:Amino Acid Sequence; D000818:Animals; D003001:Cloning, Molecular; D003435:Crotalid Venoms / Q000201:enzymology*; D018076:DNA, Complementary / Q000235:genetics; D004229:Dithiothreitol / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004487:Edema / Q000139:chemically induced; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006461:Hemolysis / Q000187:drug effects; D051379:Mice; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010713:Phosphatidylcholines / Q000378:metabolism; D010741:Phospholipases A / Q000235:genetics* / Q000302:isolation & purification / Q000633:toxicity*; D010974:Platelet Aggregation / Q000187:drug effects; D010975:Platelet Aggregation Inhibitors / Q000302:isolation & purification / Q000633:toxicity; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity; D017841:Trimeresurus
D003435:Crotalid Venoms; D018076:DNA, Complementary; D004791:Enzyme Inhibitors; D010713:Phosphatidylcholines; D010975:Platelet Aggregation Inhibitors; D010741:Phospholipases A; D004229:Dithiothreitol