Purification, characterization and structural study of the neuro-peptides from scorpion Buthus martensi Karsch

Abstract

Total 40 peptides were purified from the venom of B. martensi Karsch, and characterized on the basis of their molecular weight (ESI-MS), N-terminal sequence (5 residues) and the toxicity to mammals and insects. Among 29 long chain peptides (60-70 residues) a novel anti-insect toxin BmKαIT1 and a new anti-mammal toxin BmK IV were identified and their primary structures were determined by Edman degradation. Besides, from 11 short chain peptides (28-40 residues), three K+ channel inhibitors were identified and their action modes were investigated by the assay in acutely dissociated rat hippocampal neurons using whole-cell patch-clamp configuration. The solution structure of BmK I, the main toxin, was determined by 2D 1H-NMR spectroscopy and molecular modeling techniques. © 1999 IUPAC.