Structural variability of neurotoxins of Orthochirus scrobiculosus scorpions from different natural habitats

To study the structural variability of the Os3 neurotoxin from the venom of scorpion Orthochirus scrobiculosus inhabiting Uzbekistan and Turkmenia, a cloning method for the family of cDNAs that encode the highly homologous Os 3-like polypeptides was developed. The Turkmenian scorpion venom was shown to contain a family of closely related Os3-like polypeptides. Mass-spectrom etry indicated that crude venoms from scorpions inhabiting these two region s of Central Asia differ in the amino acid composition of their toxic compo nents depending on the habitat.