title: Purification and properties of an antivenom factor from the plasma of the South American rattlesnake (Crotalus durissus terrificus).
abstract: The lethal toxicity of Crotalus durissus terrificus (Crotalinae, Viperidae) can be attributed mainly to the presence of a neurotoxic protein, crotoxin, which also shows phospholipase A2 activity. It has been previously demonstrated that both lethal and phospholipase A2 activities of crotoxin can be neutralized by an alpha 1-globulin factor that is present in the homologous blood. Crotalus durissus terrificus plasma also renders some degree of protection to mice against the lethal toxicity of heterologous venoms from snakes of the genus Bothrops (Crotalinae, Viperidae), but not of the genus Micrurus (Elapinae, Elapidae). An anti-toxic factor was purified to homogeneity from C.d. terrificus plasma after three chromatographic steps (DEAE-Sephacel anion exchange, CM-Sepharose cation exchange and Pro-RPC reverse phase chromatography); it is named CNF for Crotalus neutralizing factor. The purification process was accompanied by polyacrylamide gel electrophoresis in the presence of SDS and by measurements of phospholipase A2 inhibition. After the first two purification steps, an 86-fold increase of the inhibitory activity of CNF was observed; however, the third step caused an apparent inactivation of the factor. The inactive CNF was shown to correspond to the previously active plasma material and to be homogeneous on electrophoresis, immunoelectrophoresis and partial amino-terminal sequence. The mol. wt of CNF was estimated as 23,600 by SDS-PAGE.
authors.affiliation: Centro de Pesquisa e Desenvolvimento, Fundacão Ezequiel Dias, Belo Horizonte, Brazil.
authors.forename: C L
authors.initials: CL
authors.lastname: Fortes-Dias
authors.forename: B C
authors.initials: BC
authors.lastname: Fonseca
authors.forename: E
authors.initials: E
authors.lastname: Kochva
authors.forename: C R
authors.initials: CR
authors.lastname: Diniz
mesh_terms: D000818:Animals; D000997:Antivenins / Q000032:analysis / Q000302:isolation & purification*; D003435:Crotalid Venoms / Q000037:antagonists & inhibitors*; D008970:Molecular Weight; D009500:Neutralization Tests; D010741:Phospholipases A / Q000037:antagonists & inhibitors; D054467:Phospholipases A2; D012911:Snakes / Q000097:blood*
chemical_list: D000997:Antivenins; D003435:Crotalid Venoms; D010741:Phospholipases A; D054467:Phospholipases A2