1. The inhibition of alkaline phosphatase by NAD(+), NADH, adenosine and nicotinamide was studied. 2. All of these substances except NAD(+) act as uncompetitive inhibitors, i.e. double-reciprocal plots are parallel. NAD(+), however, is a ;mixed' inhibitor of alkaline phosphatase and is less potent than NADH. 3. Inhibition studies with pairs of the inhibitors suggest that, in spite of the differ...

Background: Oral squamous cell carcinoma is a major cause of cancer-related deaths world-wide. Histologically it arises from the benign squamous epithelium lining the oral cavity and is conventionally divided into well, moderate, and poorly differentiated subtypes. Nicotinamide phosphoribosyltransferase catalyses the rate-limiting step of nicotinamide adenine dinucleotide synthesis and is highl...

With "reactive" arginine as a kinetic reporter, 2-hydroxyacid dehydrogenases are assessed in basis of their specialization as NAD(+)-reducing or NADH-oxidizing enzymes. Specifically, M4 and H4 lactate dehydrogenases (LDHs) and cytoplasmic and mitochondrial malate dehydrogenases (MDHs) are compared to assess if their coenzyme specificity may involve electrostatics of cationic or neutral nicotina...

Enzymatic splitting of diphosphopyridine nucleotide (DPN)’ by microorganisms, plants, and animal tissues has been known for many years, but the precise nature of this reaction is not well understood (1). Ohlmeyer (2) first observed that adenylic acid (5-phosphoadenosine) appeared when DPN was incubated with yeast maceration juice. Later Heiwinkel (3) identified adenylic acid as a product of the...

Two previously unreported metabolites of nicotinamide have been discovered as urinary excretion products of rats following intraperitoneal injection of nicotinamide-7-i4C or nicotinic acid-7-W. These compounds have been identified as 6-hydroxynicotinamide and 6-hydroxynicotinic acid by comparison of ultraviolet, infrared, and mass spectra and behavior on chromatography and electrophoresis with ...

with nicotinamide. J Lab Clin Med 1950;36: 249–58. [6] (a) El Ridi MS, Abdel Kader MM, Habib A. The role of the liver and kidney in the metabolism of nicotinamide in pellagrins and nonpellagrins. Acta Physiol Acad Sci Hung 1960;17:429–41; (b) Pasquariello G. Tryptophan-nicotinic acid pathway in diabetes mellitus. Acta Vitaminol 1964;18(5): 225–34; (c) Matsuura T, Miyata I, Kurata H. Nicotinamid...

Submitochondrial particles from mung bean mitochondria (Phaseolus aureus) are able to catalyze an energy-linked reduced nicotinamide adenine dinucleotide-nicotinamide adenine dinucleotide phosphate transhydrogenase reaction supported by ATP or by aerobically generated high energy intermediates. The energy transfer pathway appears to differ from that utilized for oxidative phosphorylation.Mung b...