VARIABILITY OF BOTHROJARACIN ISOFORMS AND OTHER VENOM PRINCIPLES IN INDIVIDUAL JARARACA (BOTHROPS-JARARACA) SNAKES MAINTAINED UNDER SEASONALLY INVARIANT CONDITIONS

Bothrojaracin (BJC) is a potent thrombin inhibitor isolated from the v enom of Bothrops jararaca. Venoms from individual snakes have been sho wn to vary in BJC content, and more than one molecular variant (isofor m) has been identified in the same venom. In order to determine whethe r the production of this protein and its isoforms varies under seasona lly invariant conditions, an analysis was made of BJC isolated from ve noms collected individually once a month for 10 months from two female B. jararaca snakes kept under conditions of constant temperature and photoperiod. The crude venom from each individual snake exhibited a ch aracteristic pattern of protein bands on sodium dodecyl sulfate-polyac rylamide gel electrophoresis (SDS-PAGE), with no noticeable variation throughout the collecting period. BJC from individual venoms was purif ied by gel filtration on Sephacryl S-200 followed by an affinity colum n (PPACK-thrombin Sepharose). BJC content and other activities such as phospholipase A(2), azocaseinolytic activity and inhibition of thromb in-induced platelet aggregation varied considerably among the samples. Purified BJC from both snakes inhibited fibrin coagulation and migrat ed as a single band of 27,000 mol. wt on SDS-PAGE. However, the BJC pa ttern on non-denaturing PAGE differed between the two snakes, with fou r to six bands per sample each month, which were all recognized by pol yclonal anti-BJC antibodies. The isoelectric focusing pattern of BJC w as also characteristic for each snake, with only minor differences thr oughout the collecting period. These results indicate that under seaso nally invariant conditions: (1) there was a considerable variation ove r the 10-month period in the production of BJC and other important ven om activities such as phospholipase A(2) and proteinases; (2) individu al B. jararaca snakes produced a distinctive array of BJC isoforms; an d (3) despite quantitative differences, there were essentially no qual itative differences in the production of BJC isoforms by individual sn akes during the 10-month period. (C) 1998 Elsevier Science Ltd. All ri ghts reserved.