Dissociation of catalytic activity and neurotoxicity of a basic phospholipase A2 from Russell's viper (Vipera russelli) venom.
A neurotoxic phospholipase A2, VRV PL-V was purified from Vipera russelli venom in a single step by CM-Sephadex C-25 column chromatography. VRV PL-V is a basic PLA2 with a mol. wt of approximately 10,000. The lethal potency of VRV PL-V was greater than that of the crude V. russelli venom. VRV PL-V showed anticoagulant activity and induced edema in the foot pad of the mouse. VRV PL-V undergoes aggregation at pH 4.8. The size of the aggregate increased as the temperature at which the enzyme was incubated was raised. A highly aggregated form with a mol. wt of 53,100 was formed at 96 degrees C. This aggregate showed a two-fold increase in its catalytic activity, while its neurotoxic activity disappeared. The aggregate also showed a significant increase in its anticoagulant activity when compared to the monomeric form. Edema-inducing activity decreased upon association to higher molecular form.
Department of Studies in Biochemistry, University of Mysore, India.
G P
GP
Jayanthi
S
S
Kasturi
T V
TV
Gowda
D000925:Anticoagulants; D002384:Catalysis; D004487:Edema / Q000139:chemically induced; D004591:Electrophoresis, Polyacrylamide Gel; D006461:Hemolysis / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D007525:Isoelectric Focusing; D007928:Lethal Dose 50; D008970:Molecular Weight; D009498:Neurotoxins; D010740:Phospholipases / Q000633:toxicity*; D010741:Phospholipases A / Q000302:isolation & purification / Q000633:toxicity*; D054467:Phospholipases A2; D013050:Spectrometry, Fluorescence; D013696:Temperature; D014757:Viper Venoms / Q000032:analysis / Q000633:toxicity*
D000925:Anticoagulants; D009498:Neurotoxins; D014757:Viper Venoms; D010740:Phospholipases; D010741:Phospholipases A; D054467:Phospholipases A2