title: Cytochrome P450 MA expression in insecticide-resistant German cockroaches (Dictyoptera: Blattellidae).
abstract: Cytochrome P450 monooxygenases are detoxification enzymes commonly involved in insecticide resistance by insects. Recently, an overexpressed form of this enzyme, P450 MA, was purified from an insecticide-resistant strain of German cockroach, Blattella germanica (L.), and polyclonal antisera (anti-P450 MA) was produced. To test hypotheses that the overexpressed condition of P450 MA has evolved in > 1 geographic location and that P450 MA might be involved in insecticide resistance to specific insecticides, investigations were conducted using 4 insecticide-resistant and 1 susceptible German cockroach strains. In western blots that used anti-P450 MA antiserum as a probe, substantial differences in expression of P450 MA were observed. Strains showing the highest P450 MA expression had both the highest tolerance to the organophosphate insecticide chlorpyrifos and cytochrome P450-mediated demethylation activity. Results support the hypothesis that cytochrome P450 MA is potentially overexpressed in insecticide-resistant populations on a global scale.
authors.affiliation: Center for Urban and Industrial Pest Management, Purdue University, West Lafayette, IN 47907-1158, USA.
authors.forename: M E
authors.initials: ME
authors.lastname: Scharf
authors.forename: C Y
authors.initials: CY
authors.lastname: Lee
authors.forename: J J
authors.initials: JJ
authors.lastname: Neal
authors.forename: G W
authors.initials: GW
authors.lastname: Bennett
mesh_terms: D000818:Animals; D020048:Blattellidae / Q000201:enzymology*; D004390:Chlorpyrifos; D003577:Cytochrome P-450 Enzyme System / Q000096:biosynthesis*; D007305:Insecticide Resistance; D007306:Insecticides; D008297:Male
chemical_list: D007306:Insecticides; D003577:Cytochrome P-450 Enzyme System; D004390:Chlorpyrifos