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Nicotinamide adenine dinucleotide phosphate hydrogen

The pentose phosphate pathway (PPP) is the major pathway for recycling nicotinamide adenine dinucleotide (NAD) to nicotinamide adenine dinucleotide phosphate hydrogen (NADPH) and for the production of ribose-5-phosphate that is needed for the synthesis of nucleotides. The function of the PPP depends on the synthesis of nicotinamide-adenine dinucleotide phosphate (NADP) and thiamin pyrophosphate, a coenzyme... [Pg.89]

Nicotinamide adenine dinucleotide (NAD and its reduced form dihydronicotinamide adenine dinucleotide (NADH)) as well as nicotinamide adenine dinucleotide phosphate (NADP and its reduced form nicotinamide adenine dinucleotide phosphate hydrogen (NADPH)) are essential co-factors for many dehydrogenases. The presence of NAD was first demonstrated in P. gallinaceum (Speck and Evans, 1945) and later studies showed increased levels of these pyridine nucleotides in P. lophurae, P. berghei and P. falciparum. Trager (1977) reported that high levels of... [Pg.258]

In oiological systems, the most frequent mechanism of oxidation is the remov of hydrogen, and conversely, the addition of hydrogen is the common method of reduc tion. Nicotinamide-adenine dinucleotide (NAD) and nicotinamide-adenine dinucleotide phosphate (NADP) are two coenzymes that assist in oxidation and reduction. These cofactors can shuttle between biochemical reac tions so that one drives another, or their oxidation can be coupled to the formation of ATP. However, stepwise release or consumption of energy requires driving forces and losses at each step such that overall efficiency suffers. [Pg.2133]

It is possible to use isolated, partially purified enzymes (dehydrogenases) for the reduction of ketones to optically active secondary alcohols. However, a different set of complications arises. The new C H bond is formed by delivery of the hydrogen atom from an enzyme cofactor, nicotinamide adenine dinucleotide (phosphate) NAD(P) in its reduced form. The cofactor is too expensive to be used in a stoichiometric quantity and must be recycled in situ. Recycling methods are relatively simple, using a sacrificial alcohol, or a second enzyme (formate dehydrogenase is popular) but the real and apparent complexity of the ensuing process (Scheme 8)[331 provides too much of a disincentive to investigation by non-experts. [Pg.12]

Nicotinic acid derivatives occur in biologic materials as the free acid, as nicotinamide, and in two coenzymatic forms nicotinamide adenine dinucleotide (NAD), and nicotinamide adenine dinucleotide phosphate (NADP). These coenzymes act in series with flavoprotein enzymes and, like them, are hydrogen acceptors or, when reduced, donors. Several plants and bacteria use a metabolic pathway for the formation of nicotinic acid that is different from the tryptophan pathway used by animals and man (B39). [Pg.199]

Dugan, R. E., Porter, J. W. Stereospecificity of the transfer of hydrogen from reduced nicotinamide adenine dinucleotide phosphate, in each of the two reductive steps catalyzed by /S-hydroxy-jS-methylglutaryl coenzyme A reductase. J. Biol. Chem. 246, 5361—5364 (1971). [Pg.67]

NADPH (nicotinamide adenine dinucleotide phosphate), 610, 643, 659 Nation membrane, hydrogen peroxide... [Pg.1474]

It is converted to coenzymes, nicotinamide adenine dinucleotide (NAD) or nicotinamide adenine dinucleotide phosphate (NADP). These coenzymes are bound to hydrogenases, function as oxidants by accepting hydrogen and electrons from substrates and become reduced. [Pg.387]

Two vitamins, nicotinamide and pyridoxine (vitamin B6), are pyridine derivatives. Nicotinamide participates in two coenzymes, coenzyme I (65 R = H) which is known variously as nicotinamide adenine dinucleotide (NAD) or diphosphopyridine nucleotide (DPN), and coenzyme II (65 R = P03H2) also called triphosphopyridine nucleotide (TPN) or nicotinamide adenine dinucleotide phosphate (NADP). These are involved in many oxidation-reduction processes, the quaternized pyridine system acting as a hydrogen acceptor and hydrogen donor. Deficiency of nicotinamide causes pellagra, a disease associated with an inadequately supplemented maize diet. Nicotinic acid (niacin) and its amide are... [Pg.155]

NAD) and nicotinamide adenine dinucleotide phosphate (NADP), are the universal carriers of hydrogen and electrons, or metabolic reducing power. Many redox processes may be linked together in electron transport chains. [Pg.304]

An important aspect of enzymatic oxidation-reduction reactions involves the transfer of hydrogen atoms. This transfer is mediated by coenzymes (substances that act together with enzymes) nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP). These two species pick up H atoms to produce NADH and NADPH, respectively, both of which can function as hydrogen atom donors. Another pair of species involved in oxidation-reduction processes by hydrogen atom transfer consists of flavin adenine triphosphate (FAD) and its hydrogenated form FADH2. The structural formulas of NAD and its cationic form, NAD+, are shown in Figure 4.7. [Pg.108]

As shown in Figure 13.3, oxidation of ascorbic acid, for example, by the reduction of superoxide to hydrogen peroxide or Fe + to Fe +, and similar reduction of other transition metal ions, proceeds by a one-electron process, forming the monodehydroascorbate radical. The radical rapidly disproportionates into ascorbate and dehydroascorbate. Most tissues also have both nicotinamide adenine dinucleotide phosphate (NADPH) and glutathione-dependent monodehydroascorbate reductases, which reduce the radical back to ascorbate. Ascorbate is thus an effective quencher of singlet oxygen and other radicals. [Pg.362]

In some cases, energy is also conserved as energy-rich hydrogen atoms in the coenzyme nicotinamide adenine dinucleotide phosphate in the reduced form of NADPH. The NADPH can then be used as a source of high-energy hydrogen atoms during certain biosynthetic reactions of anabolism. [Pg.298]

Hydrogen resulting from the photolysis of water to be used eventually for the reduction of CO2 is first bound to the coenzyme nicotinamide adenine dinucleotide phosphate (NADP). [Pg.468]

However, the saccharides (CH20) are not produced by the photoreaction but by a subsequent dark reaction of the photochemically generated hydrogenated nicotinamide adenine dinucleotide phosphate (172) (NADP -H2). [Pg.473]


See other pages where Nicotinamide adenine dinucleotide phosphate hydrogen is mentioned: [Pg.80]    [Pg.213]    [Pg.271]    [Pg.131]    [Pg.67]    [Pg.148]    [Pg.317]    [Pg.417]    [Pg.374]    [Pg.80]    [Pg.213]    [Pg.271]    [Pg.131]    [Pg.67]    [Pg.148]    [Pg.317]    [Pg.417]    [Pg.374]    [Pg.1163]    [Pg.522]    [Pg.576]    [Pg.248]    [Pg.1163]    [Pg.377]    [Pg.1085]    [Pg.326]    [Pg.24]    [Pg.621]    [Pg.153]    [Pg.359]    [Pg.381]    [Pg.439]    [Pg.169]    [Pg.144]    [Pg.465]    [Pg.2245]    [Pg.3859]    [Pg.439]    [Pg.54]   
See also in sourсe #XX -- [ Pg.80 ]

See also in sourсe #XX -- [ Pg.258 ]




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Adenine dinucleotide phosphate

Dinucleotide

Hydrogen Nicotinamide adenine

Hydrogen dinucleotide

Hydrogen phosphate

Nicotinamide adenine

Nicotinamide adenine dinucleotid

Nicotinamide adenine dinucleotide

Nicotinamide adenine dinucleotides

Nicotinamide dinucleotide

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