Molecular cloning and biochemical characterization of the first Na+-channel α-type toxin peptide (Acra4) from Androctonus crassicauda scorpion venom

► A novel toxin (Acra4) was purified from the venom of scorpion Androctonus crassicauda of Turkey. ► This peptide has 64 amino acid residues, four disulfide bridges with molecular weight of 6937 Da. ► It affects Na+ permeability of F11 cell lines, similar to other alpha-scorpion toxin peptides. ► From a cDNA library 4 additional genes similar to Acra4 were obtained and analyzed. ► Sequence comparison with other scorpion toxins are reported for the 5 novel peptides.