Genetic and biochemical studies of the highly active esterases A′ and B associated with organophosphate resistance in mosquitoes of theCulex pipienscomplex

✍ Scribed by Nicole Pasteur; Arata Iseki; George P. Georghiou

• Publisher: Springer
• Year: 1981
• Tongue: English
• Weight: 469 KB
• Volume: 19
• Category: Article
• ISSN: 0006-2928
• DOI: 10.1007/bf00504256

✦ Synopsis

The highly active esterases A' and B that cannot be dissociated from OP resistance in Culex pipiens from France and California are shown to have equivalent Km values (2.1 x 10(-6) M/min/mosquito) but different turnover rates (Vm = 2.13 and 0.57 x 10(-6) M/min/mosquito, respectively) and pH for maximum activity. Both enzymes have broad substrate specificities and at least one, esterase A', can hydrolyze OP insecticides. In addition, esterases A' and B are coded by two closely linked genes, Est-3 and Est-2, respectively (0.67 unit of crossing over), located on the same autosome as pl, a locus attributed to linkage group III. The estimated distance between Est-2 and pl was 9.4 units.