Insecticidal effects of Buthus occitanus tunetanus BotIT6 toxin expressed in Escherichia coli and baculovirus/insect cells.
BotIT6 is a neurotoxin polypeptide derived from the venom of the scorpion Buthus occitanus tunetanus (Bot). Its mature form is composed of 62 amino acids. BotIT6 has been reported to be the most potent toxin from Bot venom that has a strict selectivity for insects. Such toxin may have potential as a potent animal-harmless tool against insects. Using RT-PCR, we isolated and sequenced a cDNA encoding 62 amino acid residues corresponding to the known amino acid sequence of BotIT6. We have expressed a recombinant active form of BotIT6 in significantly high amounts in Escherichia coli. We have also engineered the cDNA into the Autographa californica Nuclear Polyhedrosis Virus (AcMNPV) genome and expressed the protein under control of the polyhedrin promoter. Supernatants of AcIT6-virus infected Sf9 insect cells exhibit a typical intoxication effect when injected to Spodoptera littoralis larvae. Moreover, injection of the recombinant virus showed enhanced insecticidal potency against S. littoralis larvae compared with wild type AcMNPV.
Bel Haj Rhouma
Rahima
R
Laboratoire des Venins et Toxines, Institut Pasteur de Tunis, Tunis-Belvedère, Tunisia.
Cérutti-Duonor
Martine
M
Benkhadir
Khadija
K
Goudey-Perrière
Françoise
F
El Ayeb
Mohamed
M
Lopez-Ferber
Miguel
M
Karoui
Habib
H
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D017931:DNA Primers; D018076:DNA, Complementary / Q000235:genetics; D004926:Escherichia coli; D015151:Immunoblotting; D007306:Insecticides / Q000633:toxicity*; D007814:Larva / Q000187:drug effects; D008969:Molecular Sequence Data; D017924:Nucleopolyhedroviruses / Q000235:genetics; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012604:Scorpion Venoms / Q000235:genetics* / Q000378:metabolism / Q000633:toxicity*; D017422:Sequence Analysis, DNA; D018411:Spodoptera / Q000187:drug effects*; D018675:Toxicity Tests
C472492:BotIT6 protein, Buthus occitanus tunetanus; D017931:DNA Primers; D018076:DNA, Complementary; D007306:Insecticides; D011994:Recombinant Proteins; D012604:Scorpion Venoms