Nicotinamide dinucleotides

Catalysis by flavoenzymes has been reviewed and various analogues of FAD have been prepared e.g. P -adenosine-P -riboflavin triphosphate and flavin-nicotinamide dinucleotide ) which show little enzymic activity. The kinetic constants of the interaction between nicotinamide-4-methyl-5-acetylimidazole dinucleotide (39) and lactic dehydrogenase suggest the presence of an anionic group near the adenine residue at the coenzyme binding site of the enzyme. ... 

Pederson, T.C., Buege, J.A. and Aust, S.D. (1973). Microsomal electron transport. The role of reduced nicotinamide dinucleotide phosphateliver microsomal lipid peroxidation. J. Biol. Chem. 248, 7134—7141. 

Activities of the RBC enzymes depend on a constant supply of reduced nicotinamide dinucleotides. Purified hemoglobin is not associated with RBC-like protection because most of the enzymes and cofactors are lost... 

In the case of enzymes involved in biochemical pathways, the isolation is often based on activity assays. The nature of the activity assay depends on the enzymatic reaction and can involve, for example, the detection of a product on a thin-layer chromatography (TLC) plate (see Chapter 4, Section 1.2.1), the appearance or disappearance of a specific absorbance in a spectrophotometric assay, or a coupled assay involving the oxidation or reduction of a co-factor such as nicotinamide dinucleotide (NAD(H)), which can be measured by changes in fluorescence. 

NADP+ NADPH NAG NAM Nicotinamide dinucleotide phosphate (oxidised form) Nicotinamide dinucleotide phosphate (reduced form) (3 - N- Acetylglucosamine ( - /V- A ce ty 1 m u r a m i c acid... 

The procedure involves precolumn oxidation of formate with formate dehydrogenase which is accompanied by a corresponding reduction of p-nicotinamideadenine dinucleotide (P(NAD)+) to reduced P-nicotinamide dinucleotide (ie P NADH). The latter is quantified by high performance liquid chromatography. See also Table 4.1. 

The Nicotinamide Dinucleotide Binding Motif and Its Reversal by Protein Engineering... 

Fig. 7. (a) The release of CF from exhaustively dialysed polyhedryl niosomes. =C16G2, solulan C24 (91 9) A=C16G2, solulan C24 (95 5) (b) The release of nicotinamide dinucleotide from polyhedral niosomes prepared from C16G2,solulan (91 9) at 24 °C. Arrow points the time at which the temperature is raised to 37 °C for 10 min... 

NADH reduced form of nicotinamide adenine dinucleotide NADP+ nicotinamide adenine dinucleotide phosphate (oxidized form) NADPH reduced form of nicotinamide dinucleotide phosphate Nj mole fraction of species) (dimensionless)... 

Gross, C., Meier, H., Papirmeister, B., Brinkley, F., Johnson, J. (1985). Sulfur mustard lowers nicotinamide dinucleotide concentrations in human skin grafted to athymic nude mice. Toxicol. Appl. Pharmacol. 81 85-90. 

The symmetrical coenzyme derivative bis-nicotinamide dinucleotide has little coenzyme activity26) and in various enzyme tests is converted at a very low rate to the symmetrical bis-dihydronicotinamide dinucleotide (Fig. 9). 

Domenech, A., Garcia, H., Marquet, J., Bourdelande, J.L., and Herance, J.R. 2006b. Modelling electrocatalysis of hydroquinone oxidation by nicotinamide dinucleotide coenzyme encapsulated within SBA-15 and MCM-41 mesoporous aluminosilicates. Electrochimica Acta 51, 4S97-490S. 

The two-domain, structural motif in FNR represents a common structural feature in a large class of enzymes that catalyze electron transfer between a nicotinamide dinucleotide molecule and a one-electron carrier. Beside the photosynthetic electron-transfer enzyme, others non-photosynthetic ones include flavodoxin reductase, sulfite reductase, nitrate reductase, cytochrome reductase, and NADPH-cyto-chrome P450 reductase. FNR belongs to the group of so-called dehydrogenases-electron transferases, i.e., flavoproteins that catalyze electron transfer from two, one-electron donor molecules to a single two-electron acceptor molecule. 

Redox potential is defined by the half cell reduction potential that is created by redox couples that are primarily due to GSH, NAD+ and nicotinamide dinucleotide phosphate. These couples are in ratios of the oxidized to reduced form of the molecules (NAD /NAD, NADP /NADPH, and GSSG/2GSH). The redox couples can be independent, as well linked to each other to form related couples. The redox environment is a reflection of these couples. These ratios can be measured by the Nemst equation, similar to a voltaic cell. 

Compounds that serve as energy carriers for the chemotrophs, linking catabolic and biosynthetic phases of metabolism, are adenosine phosphate and reduced pyridine nucleotides (such as nicotinamide dinucleotide or NAD). The structure of adenosine triphosphate (ATP) is shown in Fig. 1. It contains two energy-rich bonds, which upon hydrolysis, yield nearly eight kcal/mole for each bond broken. ATP is thus reduced to the diphosphate (ADP) or the monophosphate (AMP) form. 

Nucleoside 2 (or 3 ),5 -diphosphates have been isolated by degradation of certain coenzymes, as well as from hydrolyzates of nucleic acids. Adenosine 3, 5 -diphosphate (see p. 320) has been isolated by enzymic hydrolysis of coenzyme A and from active sulfate (adenosine 3 -phosphate 5 -phosphosulfate). Adenosine 2, 5 -diphosphate was shown to be present in the adenylic acid moiety of the coenzyme adenine-nicotinamide dinucleotide phosphate which, by treatment with a 5 -nucleotidase from potatoes, is converted into adenosine 2 -phosphate. Adenosine 3, 5 -di-phosphate is reported to play a role as a cofactor in the bioluminescence of Renilla reniformis (pansy) Ribonucleic acid carrying a terminal 5 -phos-phate group yields ribonucleoside 3, 5 -diphosphates on digestion with phosphoesterases. ... 

Nitrosyl chloride in iV,iV-dimethylfonnamide at low temperature has been used for the convenient deamination of adenosine, adenosine 5 -phosphate, adenosine 5 -triphosphate, and their iV -oxides to the corresponding inosine derivatives. Nitrous anhydride (N2O3) has been used to convert the coenzyme adenine-nicotinamide dinucleotide into hypo-xanthine-nicotinic acid dinucleotide. 

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