Post-Translational Modifications of the Sulfhydryl Group of the Cysteine Residue of Glyceraldehyde-3-phosphate Dehydrogenase

Abstract

The main types of oxidative post-translational modifications of the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDН) targeting the sulfhydryl group of the catalytic cysteine residue Cys152 are reviewed. The highly reactive sulfhydryl group of Cys152 in the active center of GAPDH undergoes oxidation and S-nitrosylation, leading to inactivation and destabilization of the enzyme. Upon reversible oxidation of the sulfhydryl group to form cysteine-sulfenic acid, the enzyme loses dehydrogenase activity, but gains the ability to catalyze the acyl-phosphatase reaction. Hydrolysis of the product of the dehydrogenase reaction, 1,3-diphosphoglycerate, under the action of oxidized GAPDH leads to uncoupling of oxidation and phosphorylation at this stage of glycolysis. The action of nitric oxide results in S-nitrosylation of Cys152 in GAPDH with the subsequent formation of cysteine-sulfenic acid due to hydrolysis of the S-NO-group. Data are presented on the relationship between S-nitrosylation, oxidation and S-glutathionylation of Cys152 in GAPDH. The role of post-translational modifications of the sulfhydryl group of the catalytic cysteine residue in the regulation of enzyme activity, as well as the mechanisms ensuring the reversibility of such modifications are discussed.