Molecular purification, and kinetic study of the enzyme glutathione peroxidase in patients with cardiovascular disease

Abstract

This study was conducted to evaluate serum glutathione peroxidase activity and partial purification of the enzyme from the serum of heart attack patients using a precipitant or what is called salting out, ion exchange dialysis using DEAE-Cellulose, and gel filtration using Sephadex G100 gel. This study was conducted on 90 samples, (60) patients whose ages ranged between (35-75) years and control (30) individuals whose ages ranged between (23-55). It showed that the number of purification times was (4.64), and the enzyme yield was (40%). The specific activity was (1.3 U/mg). Likewise, kinetic studies were carried out in which values of Km and Vmax of glutathione peroxidase were (16.66 mM) of Vmax, and (0.909 IU/L) of Km, and the optimal concentration of the base material was (100 mmol/L). The optimal temperature for enzyme action was (37°C), while the optimal pH was (7.2), and the molecular weight of glutathione peroxidase was (23 kDa). The study also studied the effect of carvedilol as an inhibitor of the enzyme glutathione peroxidase, and the results showed a decrease in enzyme activity, and the type of inhibition was uncompetitive.