Mildly oxidized glyceraldehyde-3-phosphate dehydrogenase as a possible regulator of glycolysis.
Influence of H2O2 on glycolysis was investigated. A hypothesis previously formulated was tested according to which a mild oxidation of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) results in uncoupling of oxidation and phosphorylation at this step of glycolysis due to acylphosphatase activity of the oxidized enzyme. Incubation of a mixture of purified glycolytic enzymes, as well as a muscle extract, in the presence of 10-100 microM H2O2 was shown to result in an increase in the rate of glycolysis. The level of lactate accumulation in the oxidized samples increased by 80-150% compared to the samples containing mercaptoethanol. No ATP was formed by the H2O2-stimulated glycolysis. Thus, H2O2 really caused uncoupling of oxidation and phosphorylation in glycolysis. A role of GAPDH oxidation in regulation of glycolysis is discussed.
Danshina
P V
PV
A. N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, Russia.
Schmalhausen
E V
EV
Avetisyan
A V
AV
Muronetz
V I
VI
D000244:Adenosine Diphosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000096:biosynthesis; D000818:Animals; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000737:chemistry* / Q000378:metabolism*; D006019:Glycolysis / Q000187:drug effects / Q000502:physiology*; D006861:Hydrogen Peroxide / Q000494:pharmacology; D007700:Kinetics; D019344:Lactic Acid / Q000378:metabolism; D009132:Muscles / Q000187:drug effects / Q000378:metabolism; D010084:Oxidation-Reduction; D010766:Phosphorylation; D011817:Rabbits; D051381:Rats
D019344:Lactic Acid; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D006861:Hydrogen Peroxide; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases