title: Isolation of neurotoxic peptides from the venom of the 'armed' spider Phoneutria nigriventer.
abstract: Three neurotoxic fractions, lethal to mice, were isolated from the venom of the spider Phoneutria nigriventer, by gel filtration and reverse phase chromatography (Phoneutria toxins 1, 2 and 3). These toxins have mol. wts in the range 6000-9000, and have different amino acid compositions and N-terminal amino acid sequences. The toxins also differ in the lethality and signs they cause in mice after intracerebro-ventricular injection. The median LD50 being respectively for the whole venom, toxins 1, 2 and 3, 47 +/- 5 micrograms, 45 +/- 4 micrograms, 1.7 +/- 0.7 micrograms and 137 +/- 10 micrograms/kg mouse. Toxins 1 and 2 induce excitatory symptoms in mice and toxin 3 a flaccid paralysis with an ED50 of 40 +/- 5 micrograms/kg mouse as measured also by intracerebro-ventricular injection. The presence in the venom of a non-neurotoxic, smooth muscle active peptide is also described.
authors.affiliation: Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
authors.forename: L
authors.initials: L
authors.lastname: Rezende Júnior
authors.forename: M N
authors.initials: MN
authors.lastname: Cordeiro
authors.forename: E B
authors.initials: EB
authors.lastname: Oliveira
authors.forename: C R
authors.initials: CR
authors.lastname: Diniz
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002850:Chromatography, Gel; D002853:Chromatography, Liquid; D005260:Female; D006168:Guinea Pigs; D007276:Injections, Intraventricular; D007928:Lethal Dose 50; D051379:Mice; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects; D009498:Neurotoxins / Q000032:analysis / Q000302:isolation & purification* / Q000633:toxicity; D010455:Peptides / Q000032:analysis / Q000302:isolation & purification* / Q000633:toxicity; D013111:Spider Venoms / Q000032:analysis*; D013112:Spiders / Q000378:metabolism*
chemical_list: D000596:Amino Acids; D009498:Neurotoxins; D010455:Peptides; D013111:Spider Venoms