title: Identification of a novel thrombin-like phospholipase A2 from Gloydius ussuriensis snake venom.
abstract: The coagulant effects of phospholipase A2 with Gln at 49 sites (Gln49-PLA2), purified from Gloydius ussurensis snake venom, were investigated on human citrated plasma and fibrinogen. Gln49-PLA2 clotted human plasma dose-dependently from 180.67 +/- 1.86 s to 19.00 +/- 0.58 s, and reduced the re-calcification time from 7.46 +/- 1.17 to 0.75 +/- 0.33 min and the prothrombin time from 12.4 +/- 0.29 s to 6.95 +/- 0.20 s, but it could not activate factor XIII, and the procoagulant effects were inhibited by heparin. The specific clotting activities of Gln49-PLA2 were equivalent to 1100 NIH thrombin U/mg on human fibrinogen, and the specific arginine esterase activity on the substrate BAEE was 1747 U/mg. Gln49-PLA2 hydrolyzed fibrinopeptide A faster than fibrinopeptide B, and the fibrinongenolytic ability was inhibited by the serine protease inhibitor phenyl-methylsulphonyl fluoride, but not by the metalloprotease inhibitor ethylenediamine tetraacetic acid. This finding demonstrates that Gln49-PLA2 is consistent with thrombin-like properties, and therefore should be a new thrombin-like serine protease.
authors.affiliation: Department of Bioscience and Biotechnology, Dalian University of Technology, Dalian, PR China.
authors.forename: Qiuyan
authors.initials: Q
authors.lastname: Zhang
authors.forename: Jingyun
authors.initials: J
authors.lastname: Wang
authors.forename: Ying
authors.initials: Y
authors.lastname: Han
authors.forename: Qun
authors.initials: Q
authors.lastname: Xie
authors.forename: Lijia
authors.initials: L
authors.lastname: An
authors.forename: Yongming
authors.initials: Y
authors.lastname: Bao
mesh_terms: D000818:Animals; D001779:Blood Coagulation Factors / Q000187:drug effects; D001780:Blood Coagulation Tests / Q000379:methods; D003435:Crotalid Venoms / Q000201:enzymology / Q000494:pharmacology*; D006801:Humans; D054467:Phospholipases A2 / Q000302:isolation & purification / Q000494:pharmacology*; D012697:Serine Endopeptidases / Q000494:pharmacology*; D017819:Viperidae
chemical_list: D001779:Blood Coagulation Factors; D003435:Crotalid Venoms; D054467:Phospholipases A2; D012697:Serine Endopeptidases