Characterization of a basic phospholipase A2-homologeu myotoxin isolated from the venom of the snake Bothrops neuwiedii (yarará chica) from Argentina.
A basic protein was isolated by CM-Sephadex C-25 chromatography from the venom of Bothrops neuwiedii from Argentina, and named B. neuwiedii myotoxin I. This protein exerted local myotoxic and edema-forming effects in mice, with potencies comparable to other myotoxins isolated from Bothrops spp. venoms. When injected by i.v. route at doses up to 4.7 mg/kg of body weight, the toxin was not lethal. In vitro, the toxin had no detectable phospholipase A2 activity on egg yolk phospholipids. B. neuwiedii myotoxin I appeared as a homodimer in sodium dodecylsulphate-polyacrylamide gel electrophoresis, with a subunit molecular weight of 15 kD. Gel immunodiffusion revealed a pattern of partial antigenic identity between the newly isolated myotoxin and myotoxin II from Bothrops asper venom. The sequence of B. neuwiedii myotoxin I was determined for the first 40 amino acid residues, showing high homology to several class II phospholipase A2 myotoxins of the Lys-49 family from crotalids. Altogether, results suggest that this toxin is a new member of the Lys-49 phospholipase A2-homologues with myotoxic, cytolytic, and edema-inducing activities.
Geoghegan
P
P
Servicio de Inmunoterapéuticos, CNCCB-ANLIS Carlos G. Malbrán, Buenos Aires, Argentina.
Angulo
Y
Y
Cangelosi
A
A
Díaz
M
M
Lomonte
B
B
D000595:Amino Acid Sequence; D000818:Animals; D001118:Argentina; D017837:Bothrops; D002852:Chromatography, Ion Exchange; D003435:Crotalid Venoms / Q000201:enzymology*; D004487:Edema / Q000139:chemically induced; D004591:Electrophoresis, Polyacrylamide Gel; D006470:Hemorrhage / Q000139:chemically induced; D005779:Immunodiffusion; D066298:In Vitro Techniques; D051379:Mice; D008969:Molecular Sequence Data; D018482:Muscle, Skeletal / Q000187:drug effects*; D009135:Muscular Diseases / Q000139:chemically induced; D010741:Phospholipases A / Q000032:analysis / Q000302:isolation & purification* / Q000494:pharmacology*; D054467:Phospholipases A2; D015996:Survival Rate
D003435:Crotalid Venoms; D010741:Phospholipases A; D054467:Phospholipases A2