Partial Biochemical Characterization Of A Fibrinogenolytic Fraction From Bothrops moojeni Snake Venom

¹Oliveira, M.C.; ¹Costa, J.de O.; ¹Hamaguchi, A.; ²Oliveira, F.; ¹Homsi-Brandeburgo, M. I.

1 Instituto de Genética e Bioquímica, 2 Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Minas Gerais, Brasil.

A very frequent group of proteases from brazilian snake venoms are fibrinogenolytic enzymes, which hydrolyze the Aa and Bb fibrinogen chains and rarely the g chain, generally causing blood incoagulability. The objective of present work was the characterization of a fibrinogenolytic fraction (D5) from Bothropsmoojeni snake venom. Crude venom was applied on DEAE-Sephacel column, equilibrated in 0,05mol/L ammonium bicarbonate buffer, pH 7.8, that resulted in five fractions named D1 to D5. The last fraction (D5) was submitted on Sephadex G-75, and resolved three subfractions: D5G1, D5G2, D5G3, that were analyzed in 14% SDS-PAGE. D5G1 showed a major protein of apparent molecular mass of 60 kDa, while D5G2 presented a single band with molecular mass around 25 kDa. Fibrinogenolytic activity upon fibrinogen were determinate. Samples of 50µL of bovine fibrinogen (1mg/mL PBS) were incubated with sub fractions (5µg) at 37ºC for 1h, pH 8.0. This activity were analyzed by 14% SDS-PAGE. D5 fraction presented high proteolytic activity on A-a and B-b fibrinogen chains, D5G1 partially degraded A-a chain, D5G2 had higher fibrinogenolytic activity degrading totally A-a and B-b chains while D5G3 didn´t show this activity. D5 Fraction did not present hemorrhagic, coagulant and defibrinogenating activities. Sub fractions from D5 showed two principal proteins in the D5G1 and D5G2, both with fibrinogenolytic activity.

Support: CNPq, CAPES and UFU.

Correspondence to: homsi@ufu.br