The Reye Macrothele (macrothele Raveni) The Structure And Function Of The Toxin

Spider venoms are rich sources of novel toxins, which are of interest as tools for studying neurophysilogy and as potential lead structure for insecticides and Pharmaceuticals. The spider Macrothele raveni was recently identified as a new species of genus Macrothele. It is distributed in the hilly areas of Guangxi, Hunan and Shichuan Province. The crude venom from Macrothele raveni was found toxic to mice. The intraperitoneal LD50 in mice was 2. 852mg/kg . By means of cation-exchange and reverse phase high performance liquid chromatography, several kinds of mammalian neurotoxic peptides were isolated from the crude venom and were named Raventoxin-I, III, IV, V. Raventoxin-I was the most abundant toxic component in the venom, the LD50 value is 0. 772mg/kg body weight. It can cause spontaneous contraction of isolated rat vas deferens smooth muscle. This toxin was composed of a single peptide chain, it consisted of 43 amino acid residues including 6 Lys and 8 Cys, its N-terminal residue was Cys, and C-terminal residue was also Cys.The complete amino acid sequence of Raventoxin-I is: NH2-Cys-Gly-Thr-Asn-Arg-Ala-Trp-Cys-Arg-Asn-Ala-Lys-Asp-His-Cys-Cys-Cys-Gly-Tyr-Ser-Cys-Val-Lys-Gly-Ile-Trp-Ala-Ser-Lys-Lys-Glu-Asp-Asp-Gly-Tyr-Cys-Trp-Lys-Lys-Phe-Gly-Gly-Cys-COOH Several protein/peptide toxins in the crude venom were also isolated. Partial amino acid sequence of Raventoxin-VIl, Raventoxin-VI2 was obtained...