[Cloning and expression of a resistant Culex gene in Escherichia coli]

Recombinant plasmid pRLB1 was constructed from detoxifying gene B1 of pesticide resistant Culex pipiens quinquefasciatus and from plasmid pRL439 contained the strong promoter PpsbA. The positive clone was identified by digestion and Southern analysis. Expression of recombinant plasmid containing esterase gene was detected. An engineered bacterium possessing high enzyme activity was obtained and immobilized. It can effectively degrade the specific substrate alpha-naphthyl acetate (alpha-NA) and beta-naphthyl of esterase enzyme. Assays showed that pesticide acetofenate (7504 an organic choride pesticide) was degraded by the immobilized cells within one hour.