The Kinectics and Inhibition Properties of Partially Purified Glutathione Transferase from the Head of Palm Weevil (Rynchophorus Phoenicis) Larva

An insect cytosolic glutathione transferase (GST) was partially purified from the head of palm weevil (Rynchophorous phoenicis) larvae using DEAE- cellulose ion exchange chromatography. The purified GST showed conjugating activity readily with 1- chloro- 2, 4 dinitrobenzene (CDNB) and the activity was inhibited by an insecticide 2, 2-dichloroethenyl dimethyl phosphate (DDVP). Palm weevil GST displayed a Michealian behavior at low (0.1-1.0 mM) substrate concentration. Km (GSH), Vmax was calculated to be 0.70 mM and 40.98 mol/min/mg whereas Km and Vmax (CDNB) was 33.2 mol/min/mg and1.55 mM respectively. GST from the head of palm weevil larva probabily possesses ability to catalyse external toxic substances and may be implicated in GST-based resistance.