Some Kinetic Properties and Inhibition of Glutathione S-Transferase from a Hybridized Wheat (Triticum aestivum L.)

Glutathione S-transferase enzymes (GSTs) play central roles in phase II detoxification of both xenobiotics and endogenous compounds in almost all living organisms. The enzyme was extracted and partially purified from wheat leaves through a procedure including ammonium sulfate fractionation followed by dialysis and gel filtration chromatography. These procedures yielded a 7.14-fold purification with 71% recovery. Optimum activity conditions-pH, temperature and ionic strength-of the enzyme were determined. Its some kinetic properties such as Vmax, KM, and kcat were calculated for GSH and CDNB substrates. The kcat/KM values of the enzyme were 603.5 for GSH and 385.3 for CDNB. The native molecular weight of the enzyme was estimated to be 52 kDa based on its mobility in gel filtration column.