Biochemistry (Moscow)

, Volume 74, Issue 3, pp 276–280

Hemolytic and anticoagulant study of the neurotoxin vipoxin and its components—basic phospholipase A2 and an acidic inhibitor

  • V. N. Atanasov
  • D. Danchev
  • M. Mitewa
  • S. Petrova


In the present study, we demonstrate for the first time that the potent neurotoxin vipoxin from the venom of Vipera ammodytes meridionalis exhibits hemolytic and anticoagulant properties. By investigating the effects of phospholipids and calcium ions on hemolysis, we established that the phospholipase A2 (PLA2) enzyme activity is responsible for the hemolytic properties. This was confirmed by chemical modification of the PLA2 active-site histidine residue with p-bromophenacylbromide. Applying different clotting assays, we show that the PLA2 is a weakly anticoagulant enzyme, which affects intrinsic tenase complex by the hydrolysis of procoagulant phospholipids, rather than by nonenzymatic mechanisms (binding to specific coagulation factors). The whole complex—vipoxin—does not affect the coagulation system.

Key words

vipoxin phospholipase A2 hemolysis anticoagulant activity 



activated partial thromboplastin time




prothrombin time


(secretory) phospholipase A2


Stypven time


thrombin time


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Copyright information

© Pleiades Publishing, Ltd. 2009

Authors and Affiliations

  • V. N. Atanasov
    • 1
  • D. Danchev
    • 2
  • M. Mitewa
    • 1
  • S. Petrova
    • 3
  1. 1.Laboratory of Biocoordination and Bioanalytical Chemistry, Department of Analytical Chemistry, Faculty of ChemistrySofia UniversitySofiaBulgaria
  2. 2.Unit of Hemostasis, Central Clinical LaboratoryMilitary Medical AcademySofiaBulgaria
  3. 3.Laboratory of Enzymology, Department of Biochemistry, Faculty of BiologySofia UniversitySofiaBulgaria

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