a lepidopteran-selective toxin (Buthus tamulus insect toxin; ButaIT) from the venom of South Indian red scorpion, Mesobuthus tamulus; a single polypeptide composed of 37 amino acids cross-linked by four disulfide bridges with high sequence homology to other short toxins such as Peptide I, neurotoxin P2, Lqh-8/6, chlorotoxin, insectotoxin I5A, insect toxin 15 and insectotoxin I1; amino acid sequence in first source