Superoxide anion plays important roles in vascular disease states. Increased superoxide production contributes to reduced nitric oxide (NO) bioactivity and endothelial dysfunction in experimental models of vascular disease. We measured superoxide production by NAD(P)H oxidase in human blood vessels and examined the relationships between NAD(P)H oxidase activity, NO-mediated endothelial function...

NAD(P)-dependent dehydrogenases differ according to their coenzyme preference: some prefer NAD, others NADP, and still others exhibit dual cofactor specificity. The structure of a newly identified archaeal homoserine dehydrogenase showed this enzyme to have a strong preference for NADP. However, NADP did not act as a cofactor with this enzyme, but as a strong inhibitor of NAD-dependent homoseri...

Nicotinamide adenine dinucleotide (NAD) is a ubiquitous biological molecule that participates in many metabolic reactions. Recent studies show that NAD also plays important roles in transcriptional regulation, longevity, calorie-restriction-mediated life-span extension and age-associated diseases. It has been shown that NAD affects longevity and transcriptional silencing through the regulation ...

The yeast Sir2 protein, required for transcriptional silencing, has an NAD(+)-dependent histone deacetylase (HDA) activity. Yeast extracts contain a NAD(+)-dependent HDA activity that is eliminated in a yeast strain from which SIR2 and its four homologs have been deleted. This HDA activity is also displayed by purified yeast Sir2p and homologous Archaeal, eubacterial, and human proteins, and de...

A century after the identification of a coenzymatic activity for NAD(+), NAD(+) metabolism has come into the spotlight again due to the potential therapeutic relevance of a set of enzymes whose activity is tightly regulated by the balance between the oxidized and reduced forms of this metabolite. In fact, the actions of NAD(+) have been extended from being an oxidoreductase cofactor for single ...

Naturally occurring NAD-independent variants of Haemophilus paragallinarum, which have been isolates from poultry showing clinical signs of infectious coryza, were used to determine their virulence using a newly developed challenge model for infectious coryza. It was established that the NAD-independent isolates belonging to a particular serogroup, were less virulent when compared to the virule...

BACKGROUND Whole-cell redox biocatalysis has been intensively explored for the production of valuable compounds because excellent selectivity is routinely achieved. Although the cellular cofactor level, redox state and the corresponding enzymatic activity are expected to have major effects on the performance of the biocatalysts, our ability remains limited to predict the outcome upon variation ...

Beyond its well-described role in cellular metabolism, intracellular nicotinamide adenine dinucleotide (NAD) levels have been shown to affect the enzymatic activity of a series of NAD-dependent enzymes, influencing biological responses such as cell survival and inflammation. Nicotinamide phosphoribosyl transferase activity has been shown to be essential for maintaining adequate intracellular NA...