Kinetic and Inhibition Studies for Glutathione Peroxidase(GPx) Isolated from Pea (Pisum sativum) Locality

Abstract

AbstractThis research is included the isolation of glutathione peroxidase(GPx) from thepea (Pisum sativum), studied the factors effecting the activity of the enzyme anddetermination of its molecular weight. One proteinous band had been isolated by gelfiltration sephadex (G-50) from the proteinous supernatant produced by ammoniumsulfate saturation(65%) after dialysis and the product from (G-50) give two bands bysephadex (G-100). It was found that the first peak (Peak A) had a high activity for(GPx). The apparent molecular weight of the isolated enzymes using gel filtrationchromatography was (89388+ 850) Dalton for GPx .The results also showed that the optimum conditions of GPx was obtained at(100μg/ml) of enzyme concentration using (25 mmol/l) of glutathione(GSH) as asubstrate, phosphate buffer (0.5 mol/l) as a buffer at pH (7.5) for (12) minutes at(40C). Using Lineweaver–Burk plot, the values of maximum velocity (Vmax) andMichaelis constant (Km) were (2.1 μmol/ min) and (1.25 mmol/l) respectively. Besideof, the study showed inhibition for antibiotics, analgesic and other types drugs on theenzyme activity, especially of psedeuphidrine and flagyl