Nicotinamide adenine dinucleotide analysis

Glucose [50-99-7] urea [57-13-6] (qv), and cholesterol [57-88-5] (see Steroids) are the substrates most frequentiy measured, although there are many more substrates or metaboUtes that are determined in clinical laboratories using enzymes. Co-enzymes such as adenosine triphosphate [56-65-5] (ATP) and nicotinamide adenine dinucleotide [53-84-9] in its oxidized (NAD" ) or reduced (NADH) [58-68-4] form can be considered substrates. Enzymatic analysis is covered in detail elsewhere (9). 

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. 

Naphthalene-2,3-dicarboxaldehyde Nicotinamide adenine dinucleotide N-Acetylneuraminic acid 4-Fluoro-7-nitrobenzoxadiazole Naphthalene-2,3-dicarboxaldehyde Nondestructive readout Near infrared Near infrared fluorescence Nuclear magnetic resonance 2-Nitrophenyl oxalate 1,1 -Oxalyldiimidazole Polycyclic aromatic hydrocarbon Principal component analysis Photosensitized chemiluminescence Pentachlorophenyl oxalate Polymerase chain reaction... 

An enzyme reactor with immobilized 3 -hydroxysteroid dehydrogenase has been successfully used for the analysis of residues of 17 -methyltestosterone in trout by high-performance liquid chromatography (HPLC) (269). Following their separation by reversed-phase chromatography, the major tissue metabolites of 17 -methyltestosterone, namely 5 -androstane-17 -methyl-3, 17 -diol, and 5 -androstane-17 -methyl-3, 17 -diol, were enzymatically modified in the presence of a coreactant, nicotinamide-adenine dinucleotide (NAD), to the corresponding ketone. The position at 3 was enzymatically oxidized, and NADH, the reduced form of NAD, was produced as a coproduct and subjected to fluorescence detection. Reoxidation of NADH to NAD provides the possibility for electrochemical detection. 

All potentials vs. screen-printed Ag/AgCl pseudo-reference, except values marked with asterisk ( ), which are vs. Ag/3M AgCl double-junction reference electrode, and values marked with dagger CfO, which are vs. saturated calomel. Abbreviations CoPC cobalt phthalocyanine, SPCE screen-printed carbon electrode, GOD glucose oxidase, MWCNT multi-walled carbon nanotubes, NAD nicotinamide adenine dinucleotide, PQQ pyrroloquinoline quinone, FIA flow injection analysis. 

When the dehydrogenases are used in analysis the method relies on measuring the change in the redox state of the cofactor, i.e. the change in the concentration of NAD or NADH. NADH is inherently more easily detected photometrically and electrochemically (see below) than its oxidized counterpart, NAD+ 13). When catalyzed by a dehydrogenase, the redox reaction of the nicotinamide adenine dinucleotides (NAD(P)+/NAD(P)H) is reversible, see Figure 1. A reaction catalyzed by a dehydrogenase can be schematically written as follows ... 

ICUMSA International Commission for Uniform Methods in Sugar Analysis NAD nicotinamide-adenine dinucleotide... 

The amount of inulin present is determined firom the reduction of nicotinamide-adenine dinucleotide, reduced form (NADH) measured as a decrease in absorbance at 340 nm. The method is calibrated with either inulin or fructose endogenous fructose in each sample is measured by incubation with an inactivated inulinase reagent. Urine samples require predilution (typically 1 in 40) before analysis. A typical between-run imprecision of less than 2% for plasma and less than 4% for urine can be obtained with an automated assay. 

Gatto et al m characterized the mechanism of L-pipecolic acid formation by cyclodeaminase RapL from L-lysine within rapamycin biosynthesis, which is a hybrid NRP—polyketide antibiotic (Figure 25(a)). RapL was characterized by biochemical assays to require cofactor nicotinamide adenine dinucleotide (NAD+) and an oxidative cyclodeamination reaction mechanism corresponding to ornithine cyclodeamination was proposed based on ESI-FTMS analysis of RapL reaction products (Figure 25(b)). 

IIIC) 1978 Wegmann, K., Rossler, O. E. Different Kinds of Chaotic Oscillations in the Belousov-Zhabotinskii Reaction, Z. Naturforschung A, vol. 33A, no. 10, 1170-1183 (III J) 1980 Willamowski, Rossler, O. E. Irregular Oscillations in a Realistic Abstract Quadratic Mass Action System, Z, Naturforsch., vol. 35a, 317-318 (IIIG) 1965 Yamazaki, L., Yokoya, K., Nakajima, R. Oscillatory Oxidations of Reduced Pyridine Nucleotide by Peroxidase, Biochim. Biophys. Res. Commun., vol. 21, 582-586 (IIIG) 1967 Yamazaki, I., Yokota, K. Analysis of the Conditions Causing the Oscillatory Oxidation of Reduced Nicotinamide-Adenine Dinucleotide by Biochem. Biophys. Acta, vol. 132, 310-320... 

Unified models. If experimental KIEs are available for several related reactions, it is possible to construct a unified model of the reaction to give the highest possible accuracy TS structures." A unified model differs from any other TS analysis only in that a single vibrational model and structure interpolation model is used to determine transition states for several different reactions of a given type. For example, the transition states of four hydrolytic and two adenosine 5 -diphosphate (ADP)-ribosylation reactions of oxidized nicotinamide adenine dinucleotide (NAD ) were determined using a unified model. The fact that this model worked for all these different reactions lent support to the correctness of each step in the process. 

T. Chow, S. Yoshida, M. Itoh, S. Hirose, and T. Takeda, Determination of Reduced Type Nicotinamide Adenine Dinucleotide by Flow Injection Analysis Using an Immobilized Enzyme Voltammetry System [in Japanese]. Bunseki Kagaku, 33 (1984) 310. 

K. Matsumoto, H. Ukeda, and Y. Osajima, Flow Injection Analysis of Reduced Nicotinamide Adenine Dinucleotide Using p-Naphthoquinone-4-Sulfonate as a Mediator. Agric. Biol. Chem., 48 (1984) 1879. 

ADH is widely used for serum ethanol assay. ADH kinetics is sophisticated due to the reversibility of reaction and the inhibition by both acetaldehyde and NADH as products. To simplify ADH kinetics, some special approaches are employed to make ADH reaction apparently irreversible on single substrate (alcohol). Thus, reaction pH is optimized to 9.2 to scavenge hydrogen ion semicabarzide at final 75 mmol/L is used to remove acetaldehyde as completely as possible final nicotinamide adenine dinucleotide (NA1>) is 3.0 mmol/L final ADH is about 50 U/L (Liao, et al., 2007a). By assigning the maximal absorbance at 340 nm for reduced nicotinamide adenine dinucleotide (NADH) by the equilibrium method to Ame and that by kinetic analysis of reaction curve to Amk, kinetic analysis of ADH reaction curve should predict Amk consistent with Am but requires some special efforts. 

An enzymatic method of analysis which employs a specific nicotinamide-adenine dinucleotide-dependent prostaglandin dehydrogenase from swine lung permits analysis of prostaglandins with a lower limit of 10 mole [72]. 

Later, an enzymatic method based on oxidation of ethanol by alcohol dehydrogenase (ADH) and nicotinamide adenine dinucleotide (NAD) followed by spectrophotometric analysis was reported. Current methods for detecting ethanol in body fluids are predominantly based on physicochemical techniques. A gas-liquid chromatographic (GLC) method is the most widespread because it is easy, rapid, and has high specificity and accuracy. Analytical methods used to determine alcohol in body fluids are siunma-rized in Table 1. 

Nicotinamide adenine dinucleotide phosphate, which occurs in oxidized (NADP+) and reduced (NADPH) forms with markedly different absorption spectra and an absorptivity similar to NAD can also be used for enzymatic analysis. Thus, Mg in serum can be measured by the oxidation reaction of isocitrate with NADP+, catalyzed by isocitrate dehydrogenase (IDH) (eqn [HI]) ... 

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