Crotoxin venom

Even snake venom has been tried. Called crotoxins, from the genus Crotalus, one of the two genera for rattlesnakes, these are neurotoxins that were found to have some sort of anticancer effect, direct or indirect, but presumably in very small concentrations. The snake in particnlar was said to be the cascabel, or Crotalus... 

Crotoxin. Main component of the snake venoms of rattlesnakes (Crotalinae). It is a complex of a basic phospholipase A2 (C. B, Mr 13 500) with an acidic protein (C. A, Mr 10000) which transports the phospholipase to its site of action, the presynaptic membrane of the neuromuscular end-plates. Poisoning leads to local pain and necrosis. Systemic sequelae are tiredness, collapse, and shock through to death. In addition to the neurotoxicity, C. also has hemolytic action. 

One type of presynaptic toxin is composed of two subunits bound together. The basic subunit has phospholipase A activity, whereas the acidic subunit has no enzymic activity. Crotoxin is the first presynaptic toxin isolated from snake venom and is also one of the most well-studied presynaptic toxins. 

Mojave toxin from Crotalus scutulatus is also structurally similar to crotoxin and is composed of two subunits (Bieber et al., 1975 Cate and Bieber, 1978). There are considerable amino acid sequence homologies between the two toxins (Aird et al., 1990). The amino acid sequence and spectroscopic properties of subunits of crotoxin are similar to other presynaptic phospholipases A from snake venoms (Aird et al., 1989a). 

Faure, G., Guillaume, J. L., Camoin, L., Saliou, B., and Bon, C. (1991). Multiplicity of acidic subunit isoforms of crotoxin, the phospholipase A2 neurotoxin from Crotalus durissus terrificus venom, results from post translational modifications. Biochemistry 30 8074-8083. 

Lennon, B. W., and Kaiser, 1.1. (1990). Isolation of a crotoxin- like protein from the venom of a South American rattlesnake (Crotalus durissus collilineatus). Comp. Biochem. Physiol 97B 695-699. 

STRUCTURE AND FUNCTION RELATIONSHIP OF CROTOXIN, A HETERODIMERIC NEUROTOXIC PHOSPHOLIPASE A FROM THE VENOM OF A SOUTH-AMERICAN RATTLESNAKE... 

EVOLUTIONARY RELATIONSHIPS OF p-NEUROTOXINS CROTOXIN CA CAN INTERFERE WITH SINGLE CHAIN p-NEUROTOXINS FROM VIPERIDAE VENOMS AND MODIFY THEIR PHYSIOLOGICAL PROPERTIES... 

Bouchier, C., Boulain, J.C., Bon, C., and Menez, A. (1991) Analysis of cDNAs encoding the two subunits of crotoxin, a phospholipase A2 neurotoxin from rattlesnake venom the acidic non enzymatic subunit derives from a phospholipase A2-like precursor. Biochim. Biophys. Acta 1088, 401-408. 

Choumet, V., Faure, G., Robbe-Vincent, A., Saliou, B., Mazie, J.C. and Bon, C. (1992) Immunochemical analysis of a snake venom phospholipase A2 neurotoxin, crotoxin, with monoclonal antibodies. Mol. Immunol.,29, 871-882. 

Faure, G., and Bon, C. (1987) Several isoforms of crotoxin are present in individual venoms from the South American Rattlesnake, Crotalus durissus terrificus. Toxicon, 25, 229-234. 

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