The myotoxin isolated from the venom of the snake Bothrops brazili has been studied in its mode of action. In the first hour of activity the myotoxin injected in the gastrocnemius muscle of white mice, induces the release of creatine kinase and lactate dehydrogenase, while by PAGE-SDS, it is shown that the incubation of miotoxin with isolated gastrocnemius muscle releases other proteins from this tissue. Moreover myotoxin produces hipercontraction, delta lesions and increases the concentration of intramuscular calcium “in vivo” and “in vitro”, which does not depend on extracellular calcium entry through dyhidropyridine receptors. This increase of calcium would explain the hipercontraction observed. Also it could trigger the activation of endogenous proteases and lipases, which would lead to muscle necrosis.

A myotoxin from the venom of the snake Bothrops brazili has been purified by ion-exchange chromatography on CM-Sephadex C-50 with 0,05 M ammonium acetate buffer pH 7. The homogeneity was evaluated by PAGE with and without SDS, immunodiffusion and immunoelectrophoresis. The myotoxin is a basic protein with 15,6% of Lys+Arg; it is not a glicoprotein, has not enzymatic activity, and corresponds to 25% of the whole venom protein. The molecular weight of the myotoxin was determined by PAGE-SDS and gel filtration chromatography. The myotoxin has 30 KDa of molecular weight and two polypeptide chains of 15 KDa each. Myotoxin produces a severe necrosis on the gastrocnemius muscle of white mice. The myotoxin does not have hemolytic nor anticoagulant activity. However, produces edema with a DEM of 32,6 mg of protein.

The myotoxin isolated from the venom of the snake Bothrops brazili has been studied in its mode of action. In the first hour of activity the myotoxin injected in the gastrocnemius muscle of white mice, induces the release of creatine kinase and lactate dehydrogenase, while by PAGE-SDS, it is shown that the incubation of miotoxin with isolated gastrocnemius muscle releases other proteins from this tissue. Moreover myotoxin produces hipercontraction, delta lesions and increases the concentration of intramuscular calcium “in vivo” and “in vitro”, which does not depend on extracellular calcium entry through dyhidropyridine receptors. This increase of calcium would explain the hipercontraction observed. Also it could trigger the activation of endogenous proteases and lipases, which would lead to muscle necrosis.

A myotoxin from the venom of the snake Bothrops brazili has been purified by ion-exchange chromatography on CM-Sephadex C-50 with 0,05 M ammonium acetate buffer pH 7. The homogeneity was evaluated by PAGE with and without SDS, immunodiffusion and immunoelectrophoresis. The myotoxin is a basic protein with 15,6% of Lys+Arg; it is not a glicoprotein, has not enzymatic activity, and corresponds to 25% of the whole venom protein. The molecular weight of the myotoxin was determined by PAGE-SDS and gel filtration chromatography. The myotoxin has 30 KDa of molecular weight and two polypeptide chains of 15 KDa each. Myotoxin produces a severe necrosis on the gastrocnemius muscle of white mice. The myotoxin does not have hemolytic nor anticoagulant activity. However, produces edema with a DEM of 32,6 mg of protein.

In this work, from the venom of Centruroides margaritatus (Gervais, 1841) (Scorpiones, Buthidae), one peptide with antibacterial activity was isolated and characterized. This peptide was isolated from 50 mg of whole venom, the purification was initially performed by chromatography on CM-Sephadex C-25 obtaining protein peaks seven. The peak III of this separation was purified by gel filtration on Sephadex G-75, yielding protein peaks two, the second of which proved to be the antibacterial peptide. This peptide represents about 3 % of whole venom protein and by PAGE-SDS, was determinate it has 7,3 kDa of molecular weight. The antibacterial peptide inhibits the growth of Bacillus cereus, Staphylococcus aureus, Pseudomonas aeruginosa y Serratia marcencens, in microplates with minimal media Davies, but in assays in Muller-Hinton agar, showed no significant inhibition halos; concluding that pe...

En este trabajo se ha aislado y caracterizado parcialmente un péptido con actividad antibacteriana del veneno del escorpión Centruroides margaritatus (Gervais, 1841) (Scorpiones: Buthidae). Este péptido fue aislado a partir de 50 mg de veneno crudo, y la purificación fue inicialmente realizada por cromatografía de intercambio iónico en CM-Sephadex C-25, obteniéndose siete picos de proteína. El pico III de esta separación fue purificado por cromatografía de filtración en Sephadex G-75, obteniéndose dos picos de proteína, de los cuales el segundo mostró ser el péptido antibacteriano. Este péptido representa aproximadamente el 3% de la proteína total del veneno y por PAGE-SDS, se determinó que tiene un peso molecular de 7,3 kDa. El péptido antibacteriano inhibe el crecimiento de Bacillus cereus, Staphylococcus aureus, Pseudomonas aeruginosa y Serratia marcencens, en micro...