Biochemical studies on the glutathione and the related enzymes• in fresh water fishes

Abstract

This investigation is concerned with the examination of the level of glutathione and its related enzymes (GST, GP and GR) in the liver, kidney and gills of Orechromis niloticus, Cyprinus carpio and Clarias lazera and to correlate the level with the capacity of the three different Nile fish species to resist pollutants, beside the purification and characterization of the major form of the detoxifying enzyme glutathione S­ transferase from Oreochromis niloticus , will contribute in the understanding of the role of this enzyme in protection of the cell.

-The concentration of GSH and the activity of GST, GR and GP enzymes in liver, kidney and gills of the three Nile fish were examined. -The GST pH profiles of the liver, kidney and gills cytosol of the three fish were exhibited optimum activity at pH 8 for the liver and between pH 7.5 and 9.0 for kidney and gills. -The effect of freezing and thawing and freeze drying on the stability of the enzyme at different concentrations of protein 0.34, 3.4 and 34 mg protein I ml and the effect of addition of DTT and PMSF were examined.