Comparative Study of Proteolytic Activities of Venom from Adult and Juvenile Species of Bothrops Alternatus

Abstract

Because of the technological advance in proteomic essays, ontogenic variations studies about snake venoms have become more relevant in the last years. The differences would be associated with differences in the snake venom protein composition and could have importance in the selection of the samples for production and control of quality of antivenoms. On the other hand, some authors suggested the use of venom from young snakes (yV) in order to purify some of the main components present in major proportions than in venom from adult snakes (aV). In this study, we compared venoms from Bothrops alternatus (yarará grande) from both stages of ontogeny, focusing on the study of the protein bands by SDS-PAGE and also on the study of proteolytic activities (metalloproteinases and serineproteases enzymes) exhibited by these venoms as the main responsible for the physiopathological action exhibited by this animal. Proteolytic activity was assessing by azocasein method, coagulant activity by citrated plasma and then, amidolytic actitivty was evaluated on BApNA. The results showed differences not only in the protein profile, but also in the enzymatic activities from young and adult snake venoms. Young snake venom coagulated the citrated plasma in the half time (6.3 s) the adult snake venom did. The relation yV/aV of proteolytic activity assessed on azocasein was 2 and 23 in the case of amydolitc action. These results highlight the differences in metalloproteinases concentration (responsible of caseinolytic activity) and especially in the serineproteinases composition (tested on BApNA), which would express in low quantities in adult snake venoms. These evidences warn about the necessity to assay the level of protection that the standart antivenom produces against a potential snakebite by young species and, at the same time, look for the development of antivenoms with pools including young and adult organisms.