Partial Purification and Some Kinetic studies of Glutathione Peroxidase (GPx) in Normal Human Plasma and Comparing with Primary Infertility Female

Abstract

This study attempts to isolate the glutathione peroxidase(GPx) from normal human plasma compared to infertility female. Three proteinous components had been isolated by gel filtration chromatography from the precipitate produced by ammonium sulfate. It was found that only the first peak had a high activity for GPx. The apparent molecular weight of the isolated GPx using gel filtration (Sephadex G-100) was (88131) dalton respectively.Maximum activity for GPx was obtained using (2.5) mmol/l of glutathione (GSH) as substrate, phosphate buffer (0.3 M/l) as a buffer at pH (6.5) for (14) minutes in incubation at (40)C. Using Line Weaver–Burk plot, the values of maximum velocity (Vmax) and Michaelis constant (Km) were (1.56 µmol/ min) and (1.1 mmol/l) respectively. The study showed the effect of some inhibitors on the enzyme activity. Paracetamol and copper sulfate possessed a noncompetitive inhibition while zinc acetate showed a competitive inhibition .