Subcellular distribution and characterization of esterase isozymes from insecticide-resistant and -susceptible strains of German cockroach (Dictyoptera: Blattellidae).
Esterases from insecticide-resistant and -susceptible strains of German cockroach, Blattella germanica (L.), were isolated and analyzed for differences in activity. The isozymes E5, E6, E7, and E8 of resistant strains indicated about two- to fivefold increases in activity compared with those of the susceptible strain. These isozymes constituted approximately 60% of the total activity in the resistant strains, whereas they contributed only about 40% activity in the susceptible strain. Subcellular distribution studies showed that most esterase activity is present in the 100,000 x g fraction of the homogenate (cytosolic). Only a small portion of activity was membrane bound. Molecular weights of the esterase isozymes calculated based on their retardation coefficients ranged between 48 and 81 kd.
Prabhakaran
S K
SK
Department of Entomology and Environment Programs, University of Nebraska, Lincoln 68583-0816.
Kamble
S T
ST
D000818:Animals; D003058:Cockroaches / Q000201:enzymology* / Q000648:ultrastructure; D004950:Esterases / Q000032:analysis / Q000378:metabolism*; D007305:Insecticide Resistance; D007306:Insecticides; D007527:Isoenzymes / Q000032:analysis / Q000378:metabolism*; D008970:Molecular Weight; D013347:Subcellular Fractions / Q000201:enzymology*
D007306:Insecticides; D007527:Isoenzymes; D004950:Esterases