Oxidative modification of lactate dehydrogenase by a non-enzymatic metal ion-catalyzed oxidation system.
Exposure of lactate dehydrogenase from rabbit muscle to the Fe(III)/EDTA/ascorbate oxidation system leads to a time-dependent enzymatic inactivation (rate of inactivation of 7.35 x 10(-3) min-1), as well as to a spontaneous fragmentation of the protein. Fe(III) is the most important compound in this system, having the highest inactivating effects at concentrations above 10 microM. The substrate pyruvate and the products of the enzymatic reaction, when added at high concentration to the full mixture of the system, have a partial protective effect on the catalytic activity.
Alonso-Llamazares
A M
AM
Departamento de Bioquímica y Biología Molecular, Universidad de León, Spain.
de Arriaga
D
D
Soler
J
J
D000818:Animals; D001205:Ascorbic Acid / Q000737:chemistry*; D002384:Catalysis; D004492:Edetic Acid / Q000737:chemistry*; D004591:Electrophoresis, Polyacrylamide Gel; D016166:Free Radical Scavengers; D006801:Humans; D007501:Iron / Q000737:chemistry*; D007770:L-Lactate Dehydrogenase / Q000737:chemistry*; D009243:NAD / Q000737:chemistry; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry*; D011773:Pyruvates / Q000737:chemistry; D019289:Pyruvic Acid; D011817:Rabbits
D016166:Free Radical Scavengers; D011773:Pyruvates; D009243:NAD; D019289:Pyruvic Acid; D004492:Edetic Acid; D007501:Iron; D007770:L-Lactate Dehydrogenase; D001205:Ascorbic Acid; D010100:Oxygen