Purification and characterization of a short insect toxin from the venom of the scorpion Buthus tamulus

FEBS Letters

Sethi, Anurag¹  Joseph, Suresh¹  Dhawan, Ritu¹  Lala, Anil K¹ 

[1] Biomembrane Lab, Department of Chemistry and School of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India

关键词: Scorpion;    Toxin;    Homology;    Insectotoxin;    Buthus tamulus;    Helicoverpa armigera;   

DOI  :  10.1016/S0014-5793(02)03326-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

A short chain peptide has been isolated from the venom of a red scorpion of Indian origin, Buthus tamulus. This peptide was purified using ion exchange and reverse phase chromatography and was characterized by molecular weight determination and amino acid sequence. The primary structure analysis shows that BtITx3 is a short peptide of 35 amino acid residues having a molecular weight of 3796 Da. The toxin shows toxicity towards the Lepidopteran species of insect Helicoverpa armigera causing flaccid paralysis and even death within 24 h. It shows more than 50% homology with the short insectotoxins having four disulfide bridges, which suggests that the toxin belongs to the class of short chain toxins blocking the chloride ion channels. This sequence homology study has also helped to bring out the structure–function relationship between the various short toxins. Homology modeling done by using template structure of a known toxin indicated that this toxin consists of a similar α/β scaffold, as present in other scorpion toxins.

【 授权许可】

Unknown