Activities for nicotinamide adenine dinucleotide (NAD)-dependent and NAD-independent forms of lactate dehydrogenase (LDH) were measured in cell-free extracts of Staphylococcus aureus strain PS 6 for the d and l isomers of lactate. Data obtained for the NAD-dependent lactate dehydrogenases indicate that oxidation of both isomers of lactate is due to both an l-lactate-specific LDH and a lactate r...

The concomitant presence of two distinctive polypeptide modules, which we have chosen to denominate as the “Y-junction” and “flavin” module, is observed in 3D structures enzymes functionally diverse complex I, NAD(P)-dependent [NiFe]-hydrogenases formate dehydrogenases. Amino acid sequence conservation furthermore suggests that both modules are also part [FeFe]-hydrogenases for no structure mod...

Overexpression of the NAD+ biosynthetic enzyme NMNAT1 leads to preservation of injured axons. While increased NAD+ or decreased NMN levels are thought to be critical to this process, the mechanism(s) of this axon protection remain obscure. Using steady-state and flux analysis of NAD+ metabolites in healthy and injured mouse dorsal root ganglion axons, we find that rather than altering NAD+ synt...

Nitric oxide-stimulated modification of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) by [adenylate-32P]NAD has been interpreted in recent reports as ADP-ribosylation. Incubations of GAPDH with the NO-releasing agent sodium nitroprusside (SNP) and NAD resulted, however, in essentially equal incorporation of radiolabel from the adenine, phosphate, and nicotinamide moieties to the extent of ap...

Cytosolic free NAD/NADH ratio is fundamentally important in maintaining cellular redox homeostasis but current techniques cannot distinguish between protein-bound and free NAD/NADH. Williamson et al reported a method to estimate this ratio by cytosolic lactate/pyruvate (L/P) based on the principle of chemical equilibrium. Numerous studies used L/P ratio to estimate the cytosolic free NAD/NADH r...

Type 1 diabetes provokes a protein kinase C (PKC)-dependent accumulation of superoxide anion in the renal medullary thick ascending limb (mTAL). We hypothesized that this phenomenon involves PKC-dependent NAD(P)H oxidase activation. The validity of this hypothesis was explored using mTAL suspensions prepared from rats with streptozotocin-induced diabetes and from sham (vehicle-treated) rats. Su...

Although NAD(+) biosynthesis is required for Sir2 functions and replicative lifespan in yeast, alterations in NAD(+) precursors have been reported to accelerate aging but not to extend lifespan. In eukaryotes, nicotinamide riboside is a newly discovered NAD(+) precursor that is converted to nicotinamide mononucleotide by specific nicotinamide riboside kinases, Nrk1 and Nrk2. In this study, we d...

NAD(+) is a central metabolite in the cell. Changes in NAD(+) abundance and the activity of NAD(+)-dependent enzymes, such as the sirtuins, are at the core of metabolic/mitochondrial diseases, such as obesity and diabetes, and of cancer and neurodegeneration. Here, we discuss how maintaining or raising NAD(+) levels can improve metabolism and prevent age-related functional decline and associate...

The capacities of Procion Red HE-3B and Cibacron Blue F3G-A immobilized to Sepharose CL-4B and Matrex 201R for NAD+-, NADP+- and NAD(P)+-dependent dehydrogenases were measured. Procion Red HE-3B columns retarded NADP+-dependent dehydrogenases more effectively than NAD+-dependent dehydrogenases, whilst immobilized Cibacron Blue F3G-A retarded NAD+-dependent dehydrogenases more effectively than N...

A triple mutant of NADP(H)-dependent malate dehydrogenase from thermotolerant Thermococcus kodakarensis has an altered cofactor preference for NAD+, as well improved production compared to wildtype dehydrogenase. By combining with glucose Sulfolobus solfataricus and NAD+/NADH in a closed reaction environment, gluconate could be produced pyruvate glucose. After 3 h, the yield was 15.96 mM. These...