title: Biochemical characterization of insecticide resistance in the German cockroach, Blattella germanica, from Malaysia.
abstract: The possible insecticide resistance mechanisms of four Malaysian field-collected strains of the German cockroach, Blattella germanica (Linnaeus) (Dictyoptera: Blattellidae), were characterized with biochemical assays and native polyacrylamide gel electrophoresis (PAGE). Elevated esterase activity (at low to moderate frequency) and altered acetylcholinesterase (low frequency) were detected in all field strains, while elevated glutathione S-transferase levels were present in only two strains. Seven esterase bands were separated by native PAGE; a greater intensity occurred in three bands in the resistant strains compared to the susceptible strain. Inhibition studies using specific inhibitors on polyacrylamide gels suggested that the slowest of these three esterases is a cholinesterase, while the other two are carboxylesterases with a preference for beta- over alpha-naphthyl acetate.
authors.affiliation: Vector Control Research Unit, School of Biological Sciences, Universiti Sains Malaysia, Penang.
authors.forename: C Y
authors.initials: CY
authors.lastname: Lee
authors.forename: J
authors.initials: J
authors.lastname: Hemingway
authors.forename: H H
authors.initials: HH
authors.lastname: Yap
authors.forename: N L
authors.initials: NL
authors.lastname: Chong
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism; D000818:Animals; D020048:Blattellidae / Q000201:enzymology*; D004591:Electrophoresis, Polyacrylamide Gel / Q000662:veterinary; D004950:Esterases / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D007300:Insect Control; D007305:Insecticide Resistance; D008296:Malaysia; D008297:Male
chemical_list: D005982:Glutathione Transferase; D004950:Esterases; D000110:Acetylcholinesterase