Zeitschrift für Chromatographie und Trenntechniken
Offener Zugang

Abstrakt

Purification and Characterization of Glutathione-S-Transferase from Rats Liver: Effect of Carbon Tetrachloride and Camels Milk

Mohamed Lebda, Nabil Taha, Saad Noeman, Mahdy Korshom, Abd El-Wahab Mandour and Ahlam El-Leboudy

Glutathione-S-transferases (GSTs) constitute a multifunctional family of dimeric and mainly cytosolic biotransformation enzymes which play an important role in protecting tissues from oxidative stress. They catalyzed the conjugation of intracellular glutathione with great varieties of chemicals possessing electrophilic centre and the final GSH-conjugates had increased hydrophilicity which facilitate their further metabolism and elimination. Our study was carried out to purify GST enzyme from rat’s liver using one step affinity chromatography and investigate the inhibitory effect of carbon tetrachloride and ameliorating effect of camel’s milk administration. The purification of GST enzyme revealed that the protein concentration decreased in GSH affinity filtrate than the crude extract while the specific enzyme activity increased indicating that the single purification step cut off the other proteins and conserve the protein of GST enzyme. CCL4 decrease the Vmax and increase Km for both GSH and CDNB substrates than control indicating that CCL4 may be uncompetitive inhibitor of GST enzyme while camel’s milk increase the Vmax and decrease Km for both GSH and CDNB substrates indicating that camel’s milk increase the affinity of enzyme to both substrates. The activity of GST increased by increasing the substrate concentration till reaching the maximum activity after which the activity of GST forming a plateau. Regarding the effect of temperature on GST activity, the maximum GST activity was observed between 25-35ºC and inactivated over 40ºC. The GST activity increased when pH increased progressively till reach the maximum activity at pH value 7.1 and decreased when the pH increased. Our conclusion indicating that CCL4 is uncompetitive inhibitor of GST enzyme while camel’s milk increases the activity and affinity of enzyme toward its both substrates.