Haemorrhagic protein of Russell's viper venom with fibrinolytic and esterolytic activities

A haemorrhagic toxin specifically active on skin and muscle at the site of introduction in mice has been purified from Vipera russelli russelli (India n subspecies of Russell's viper) venom by CM-Sephadex C-50 ion exchange chr omatography and size exclusion (SE)HPLC. This toxic protein also has strong fibrinolytic and arginine esterolytic activities. The purified preparation was a single polypeptide chain of molecular weight 73,000, as revealed by SDS-PAGE and SE-HPLC under native and denatured conditions. It has been nam ed as VRR-73. Atomic absorption spectrometry indicated the existence of Mg2 + in a mol per mol ratio. Antiserum was effective in neutralizing haemorrha ge when administered immediately following VRR-73 but was ineffective in in hibiting fibrinolytic and esterolytic activities. On the other hand phenylm ethyl sulphonyl fluoride and EDTA inhibited fibrinolysis and esterolysis bu t did not affect haemorrhage. Thermal denaturation of VRR-73, after exposur e at 100 degrees C for 10 min, led to inactivation of all of its activities . Fibrinolytic and esterolytic activities, but not the haemorrhagic activit y, were slowly regained after cooling at 25 degrees C. Thus the two patholo gical activities of VRR-73 appear to be associated with two different regio ns of the molecule. (C) 2000 Elsevier Science Ltd. All rights reserved.