title: New esterase enzymes involved in organophosphate resistance in Culex pipiens (Diptera: Culicidae) from Guang Zhou, China.
abstract: Organophosphate (OP) insecticides have been used widely to control Culex pipiens L. populations and this has led to the emergence of OP-resistance. Predominantly, resistance in Cx. pipiens is caused by over-production of nonspecific esterases, such as Est beta 1(1) and Est alpha 2(1)/beta 2(1). These esterases confer multiple resistance to organophosphorus and carbamate insecticides. To define the esterases in Chinese Cx. pipiens, restriction fragment-length polymorphism analysis was performed at the esterase beta locus. A new esterase haplotype (Est beta 8) was found. Starch gel electrophoresis indicated that Est beta 8 was coelevated with a novel Est alpha 8. This article reports Est alpha 8/beta 8 esterase-mediated resistance in Cx. pipiens complex.
authors.affiliation: State Key Laboratory of Integrated Management of Pest Insects and Rodents, Academia Sinica, Beijing, China.
authors.forename: C L
authors.initials: CL
authors.lastname: Qiao
authors.forename: Z Q
authors.initials: ZQ
authors.lastname: Sun
authors.forename: J E
authors.initials: JE
authors.lastname: Liu
mesh_terms: D000818:Animals; D002219:Carbamates; D002681:China; D003465:Culex / Q000201:enzymology*; D004006:Dichlorvos; D004351:Drug Resistance; D004592:Electrophoresis, Starch Gel; D004950:Esterases / Q000302:isolation & purification / Q000378:metabolism*; D007305:Insecticide Resistance; D007306:Insecticides; D008743:Methyl Parathion
chemical_list: D002219:Carbamates; D007306:Insecticides; C019276:BPMC; D008743:Methyl Parathion; D004006:Dichlorvos; D004950:Esterases