NADP"

Indicators There are certain compounds that are suitable as indicators for sensitive and specific clinical analysis. Nicotinamide adenine dinucleotide (NAD) occurs in oxidized (NAD" ) and reduced (NADH) forms. Nicotinamide adenine dinucleotide phosphate (NADP) also has two states, NADP" and NADPH. NADH has a very high uv—vis absorption at 339 nm, extinction coefficient = 6300 (M cm) , but NAD" does not. Similarly, NADPH absorbs light very strongly whereas NADP" does not. 

The second en2ymatic reaction converts NADP" to NADPH and and the appearance of NADPH is measured at 340 nm. 

Fig. 4. The cycle of events involved in cytochrome (Cyt) P q (Cyt P450 Fe + ) mediated dmg metaboHsm where NADP is nicotinamide disphosphate and...

NADP = nicotinamide-adenine dinucleotide phosphate NADPH = reduced nicotinamide—adenine dinucleotide phosphate NDP = nucleoside... 

Nicotinamide and nicotinic acid occur in nature almost exclusively in the bound form. In plants, nicotinic acid is prevalent whereas in animals nicotinamide is the predominant form. This nicotinamide is exclusively in the form of NAD and NADP. 

NAD and NADP are required as redox coen2ymes by a large number of enzymes and ia particular dehydrogenases (Fig. 6). NAD" is utilized ia the catabohe oxidations of carbohydrates, proteins, and fats, whereas NADPH2 is the coenzyme for anaboHc reactions and is used ia fats and steroid biosynthesis. NADP+ is also used ia the cataboHsm of carbohydrates (2). 

NAD" — see Nicotinamide adenine dinucleotide NADP" — see Nicotinamide adenine dinucleotide phosphate NADPH... 

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. 

Nicotinamide adenine dinucleotide phosphate (NADP, TPN) [53-59-8] M 743.4, pK] 1.1 (PO4H2), pK 4.0 (adenine NH ), pKa 6.1 (P04 ). Purified by anion-exchange chromatography in much the same way as for NAD [Dalziel and Dickinson Biochem J 95 311 7965 Biochemical Preparations 11 87 7966]. Finally it is purified by dissolving in H2O and precipitating with 4 volumes of Me2CO and dried in... 

Nicotinamide adenine dinucleotide phosphate reduced tetrasodium salt (reduced diphosphopyridine nucleotide phosphate sodium salt, NADPH) [2646-71-1] M 833.4, pK as for NADP. Mostly similar to NADH above. 

The United States has established a National Acid Deposition Program (NADP), and Canada has established the CANSAP program, which consists... 

Fig. 14-9. Wet/dry precipitation collector and flow chart for analysis of samples. (DI HjO distilled water). Source "NADP Quality Assurance Report," Central Analytical Laboratory, Illinois Institute of Nafural Resources, Champaign, 111., March 1980.

Riboflavin (vitamin Bg) Nicotinamide adenine dinncleotide phosphate (NADP+) Flavin adenine dinncleotide (FAD)... 

Nicotinamide is an essential part of two important coenzymes nicotinamide adenine dinucleotide (NAD ) and nicotinamide adenine dinucleotide phosphate (NADP ) (Figure 18.19). The reduced forms of these coenzymes are NADH and NADPH. The nieotinamide eoenzymes (also known as pyridine nucleotides) are electron carriers. They play vital roles in a variety of enzyme-catalyzed oxidation-reduction reactions. (NAD is an electron acceptor in oxidative (catabolic) pathways and NADPH is an electron donor in reductive (biosynthetic) pathways.) These reactions involve direct transfer of hydride anion either to NAD(P) or from NAD(P)H. The enzymes that facilitate such... 

FIGURE 18.20 NAD and NADP participate exclusively iii two-electroii transfer reactions. For example, alcohols can be oxidized to ketones or aldehydes via hydride transfer to NAD(P). ... 

The NAD- and NADP-dependent dehydrogenases catalyze at least six different types of reactions simple hydride transfer, deamination of an amino acid to form an a-keto acid, oxidation of /3-hydroxy acids followed by decarboxylation of the /3-keto acid intermediate, oxidation of aldehydes, reduction of isolated double bonds, and the oxidation of carbon-nitrogen bonds (as with dihydrofolate reductase). 

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