Isoenzymes of Aedes albopictus (Diptera: Culicidae) Glutathione S-transferases: Isolation and expression after acute insecticide treatment

Glutathione S-transferases (GSTs) from susceptible Aedes albopictus larvae were partially isolated using two different purification strategies (GSTrap™ HP and GSH-agarose affinity columns) and the effects of permethrin and DDT on expression of the GSTs were investigated. Distinct double bands on SDS-PAGE with molecular weights between 20 and 25 kDa were successfully purified using GSTrap™ HP while a single band of 24.5 kDa was purified using GSH-agarose. The isolated GSTs belonged to the Delta, Sigma and Theta GST classes. When exposed to permethrin, one isoform of Theta, four isoforms of Sigma and thirteen isoforms of Delta GSTs showed an increased expression between 1.4-fold and 2.5-fold while DDT treatment resulted in between 1.4-fold and 3.2-fold increased expression in one isoform of Theta, four isoforms of Sigma and eleven isoforms of Delta GSTs (p