THE EFFECT OF pH, TEMPERATURE, ANTIVENIN AND FUNCTIONAL GROUP INHIBITORS ON THE TOXICITY AND ENZYMATIC ACTIVITIES OF CROTALUS ATROX VENOM

摘要

To determine the effects of certain group-specific reagents on the toxicity of Crotalus atrox (Western diamondback rattlesnake) ven¬om and the effect of pH, temperature, and antivenin on the toxicity and enzymatic activities of this venom.nCrotalus atrox venom has been completely detoxified by 50 mM N-bromosuccinimide. This venom cannot be detoxified with the sulfhydryl group reagents, N-ethylmaleimide or iodoacetamide, or the metal-binding agent EDTA. It is very slightly detoxified by reaction with O-methylisourea, diisopropylfluorophosphate, or British anti-lewisite. The toxic principle in C. atrox venom is resistant to low pH treatment, but is destroyed by heating at 7 5° for one hour. Under the same conditions the following enzymes are destroyed: phosphodi¬esterase, esterase (TAMEase), and proteolytic enzyme activity on azocoll, congocoll, casein, and N-benzoyl-DL-arginine p-nitroanilide. Phospholipase A activity is only partially destroyed under these con¬ditions.nThe effects observed on various enzymes with functional group inhibitors and the results of the heat inactivation and acid treatment of C. atrox venom indicate that the main toxicity of this venom is not associated with the enzymatic components but may reside with a pep¬tide of relatively low molecular weight.nAttempts should be made to separate the proteolytic, phospho¬lipase A, anticoagulant and toxic activities of C. atrox venom and their physiological effects determined in order to learn whether the toxicity of this venom is due ,to separated toxin(s) or a synergistic action of one or more enzymes. Detoxification with N-bromosuccinimide and antibody production should be studied with the detoxified ven¬om produced.