title: Assesment of metal inhibition of antioxidant enzyme glutathione reductase from rainbow trout liver.
abstract: Effects of Co(+2), Zn(+2), Ca(+2), Fe(+2), Mn(+2), Cr(+3), Sn(+2) and Mg(+2) exposure of rainbow trout liver on the enzymatic activity of glutathione reductase (GR) were investigated. GR was purified from rainbow trout liver 1419-fold with a yield of 38.41% and a specific activity of 22.846 U/mg protein. Following enzyme isolation, inhibitory effects of Co(+2), Zn(+2), Ca(+2), Fe(+2), Mn(+2), Cr(+3) and Sn(+2) were analysed. IC(50) values of the metal ions ranged from 42.2 to 657 µM, and the K(i) constants ranged from 24.2 to 567µ. Co(+2), Zn(+2), Fe(+2) and Cr(+3) exhibited competitive inhibition whereas others inhibited the enzyme in non-competitive manner. Cobalt was the most powerful inhibitor among others having the lowest IC(50) and K(i) values. Magnesium exhibited activatory effect on the enzyme.
authors: Ondokuz Mayıs University, Faculty of Agriculture, Department of Agricultural Biotechnology, Samsun, Turkey.
authors: Deniz
authors: D
authors: Ekinci
authors: Murat
authors: M
authors: Şentürk
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D002846:Chromatography, Affinity / Q000379:methods; D003035:Cobalt / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005980:Glutathione Reductase / Q000037:antagonists & inhibitors* / Q000302:isolation & purification; D020128:Inhibitory Concentration 50; D008099:Liver / Q000187:drug effects / Q000201:enzymology*; D008274:Magnesium / Q000494:pharmacology; D008670:Metals / Q000494:pharmacology*; D017686:Oncorhynchus mykiss / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000494:pharmacology
chemical_list: D000975:Antioxidants; D004791:Enzyme Inhibitors; D008670:Metals; D014874:Water Pollutants, Chemical; D003035:Cobalt; D005980:Glutathione Reductase; D008274:Magnesium