Abstract: Although it has been suggested that CYP6B7 in the cotton bollworm, Helicoverpa armigera, is probably responsible for resistance to pyrethroids, there is no direct evidence showing that CYP6B7 is involved in the metabolism of pyrethroid pesticides. To explore the function of CYP6B7 gene, we attempted to produce CYP6B7 enzyme through heterologous expression of the CYP6B7 gene. The open reading frame of CYP6B7 gene was isolated by PCR with genomic DNA as the template and using a pair of CYP6B7 gene specific primers, followed by reverse PCR aiming at deleting the intron sequence of 321 bp. A fusion plasmid (CYP6B7-pMAL) was constructed by inserting the CYP6B7 gene into the BamHⅠ-SalⅠ restriction sites of pMAL-c2X vector. CYP6B7 pMAL plasmid was transformed into E. coli TB1. A fusion protein (CYP6B7 fused with maltose binding protein) was expressed after induction by IPTG..SDS-PAGE pure fusion protein was isolated with an amylose column.

Key words: Helicoverpa armigera, cytochrome P450, CYP6B7, gene cloning, fusion expression