Has both glyceraldehyde-3-phosphate dehydrogenase and nitrosylase activities, thereby playing a role in glycolysis and nuclear functions, respectively. This leads to reduced ubiquitination of TRAF2 and TRAF3, and subsequent inhibition of NF-kappa-B signaling and type I interferon production, respectively. (Microbial infection) Glycosylated by C.rodentium protein NleB, enteropathogenic E.coli protein NleB1 and S.typhimurium protein Ssek1: arginine GlcNAcylation prevents the interaction with TRAF2 and TRAF3. It was proposed that the S-(2-succinyl)cysteine chemical modification may be a useful biomarker of mitochondrial and oxidative stress in diabetes and that succination of GAPDH and other thiol proteins by fumarate may contribute to the metabolic changes underlying the development of diabetes complications. Fumarate concentration as well as succination of cysteine residues in GAPDH is significantly increased in muscle of diabetic mammals. Succination of Cys-152 and Cys-247 by the Krebs cycle intermediate fumarate, which leads to S-(2-succinyl)cysteine residues, inhibits glyceraldehyde-3-phosphate dehydrogenase activity. This cascade of oxidations may augment GAPDH misfolding, leading to intermolecular disulfide cross-linking and aggregation. It has been proposed to destabilize nearby residues, increasing the likelihood of secondary oxidative damages, including oxidation of Tyr-45 and Met-105. This modification has been detected in vitro following treatment with free radical donor (+/-)-(E)-4-ethyl-2-(E)-hydroxyimino-5-nitro-3-hexenamide. Oxidation at Met-46 may play a pivotal role in the formation of these insoluble structures. Such aggregates can be observed in vivo in the affected tissues of patients with Alzheimer disease or alcoholic liver cirrhosis, or in cell cultures during necrosis. Oxidative stress can promote the formation of high molecular weight disulfide-linked GAPDH aggregates, through a process called nucleocytoplasmic coagulation. Sulfhydration at Cys-152 increases catalytic activity. S-nitrosylation of Cys-247 is induced by interferon-gamma and LDL(ox) implicating the iNOS-S100A8/9 transnitrosylase complex and seems to prevent interaction with phosphorylated RPL13A and to interfere with GAIT complex activity. S-nitrosylation of Cys-152 leads to interaction with SIAH1, followed by translocation to the nucleus.
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