Mechanism of oxidative damage of dog kidney Na/K-ATPase.
Oxidative modification of kidney Na/K-ATPase was found to be accompanied by a decrease in the amount of sulfhydryl groups accessible for Elmann reagent with subsequent transformation of kinetic behavior of the enzyme. Oxidation of Na/K-ATPase with 20 mM hydrogen peroxide during 20 min results in about 50% inhibition of its activity and subsequent transformation of complex substrate-velocity dependence into the simple hyperbolic curve. In terms of kinetic analysis the suggestion was made that partial oxidation of Na/K-ATPase by hydrogen peroxide results in disordering of interprotomer interaction in the oligomeric complex of Na/K-ATPase.
Boldyrev
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A
International Biotechnological Center, Moscow State University, Russia. boldyrev@inevro.msk.su
Kurella
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E
D000818:Animals; D004285:Dogs; D004372:Ducks; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D007668:Kidney / Q000201:enzymology*; D007700:Kinetics; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D012491:Salt Gland / Q000201:enzymology; D000254:Sodium-Potassium-Exchanging ATPase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D013438:Sulfhydryl Compounds / Q000032:analysis
D013438:Sulfhydryl Compounds; D006861:Hydrogen Peroxide; D000254:Sodium-Potassium-Exchanging ATPase