Purification, cDNA cloning and function assessment of BmK abT, a unique component from the Old World scorpion species

摘要: A new neurotoxic component named BmK abT was purified from the venom of Chinese scorpion Buthus martensi Karsch. The molecular weight determined to be 7212 Da on a mass spectrum. minimum lethal dose tested about 1.5 μg per mouse by intracerebroventricular injection, and induced significant paralysis effect cockroach 5 i.p. injection. partial amino acid sequence indicated that it distinctive polypeptide in neurotoxin family. Thereafter, whole mature deduced cDNA 5′- 3′-rapid amplification ends. Finally, defined composed 63 residues with amidation at C-terminal residue. By comparison, found most similar Ts VII, β-toxin New World scorpion. patch-clamp recording DRG neurons, unexpectedly, showed this toxin could prolong action potential increase amplitude peak Na+ currents, which are typical characters α-toxin. These results suggested toxic Old species structurally β-toxins, but functionally α-toxins.