Nicotinamide diaphorase

Poeggel, G., Lange, E., Hase, C., Metzger, M., Gulyaeva, N., and Braun, K. (1999) Maternal separation and early social deprivation in Octodon degus quantitative changes of nicotinamide adenine dinucleotide phosphate-diaphorase-reactive neurons in the... 

Human populations that have experienced health effects from exposure to 2-nitrophenol or 4-nitrophenol have not been identified, but little research has been conducted on this subject. Based on results from animal studies, as described in Section 2.6, it is possible that individuals who consume ethanol may have slower rates of clearance of 4-nitrophenol. This subpopulation, if exposed to 4- nitrophenol, may be considered potentially susceptible. Furthermore, newborn infants utilize fetal hemoglobin, which has reduced oxygen-carrying capacity, and also have low levels of nicotinamide adenine dinucleotide diaphorase, which continuously reduces methemoglobin therefore, infants (as well as individuals congenitally deficient in this enzyme) may represent... 

Akbarian S, Bunney WE Jr, Potkin SG, Wigal SB, Hagman JO, et al. 1993a. Altered distribution of nicotinamide-adenine dinucleotide phosphate-diaphorase cells in frontal lobe of schizophrenics implies disturbances of cortical development. Arch Gen Psychiatry 50 169-177. 

In addition to transfer of hydrogen between various nicotinamide nucleotides, the transhydrogenases from Pseudomonas 17), spinach 11, 13), and Azotobacter 9, 19) also catalyze a diaphorase reaction, using either NADH or NADPH plus an artificial acceptor, e.g., potassium fer-ricyanide or dichlorophenolindophenol. As expected, 2 -AMP stimulates the NADH-linked diaphorase reaction catalyzed by the Pseudomonas enzyme 17). 

Boger m) showed that the transhydrogenase activity catalyzed by ferredoxin-NADP reductase obtained from Bumilleriopsis filiformis, which is very similar to the spinach enzyme, is regulated by ferredoxin and that one common nicotinamide nucleotide binding site is involved in both the diaphorase and the transhydrogenase reactions. 

Nicotinamide adenine dinucleotide Tetrazolium violet Diaphorase... 

Alternatively, glycerophosphate is measured in a reduced form of nicotinamide-adenine dinucleotide (NADH)-producing reaction and the NADH measured by a spectrophotometer set at 340nm or in a diaphorase-catalyzed reaction to form a reaction product whose absorbance is measured at 500 nm. 

Often the electron transfer between the reduced nicotinamide coenzyme and the mediator is rather slow because of kinetic limitations. In many of these cases electron transfer catalyzed by diaphorase (E. C. 1.6.99.x) results in a drastic enhancement of the reaction rate (Fig. 16.2-5 C). Diaphorase-catalyzed NAD(P)+ regeneration was reported for example with methylene blue1321, PQQ1331 (under aerobic conditions), ferrocene(28), N -methyl-p-aminophenol(34 , N, N-dimethylindoaniline, 2,6-di-chlorophenol indophenol (DCIP), [Fe(CN)6]2 [351, viologenes or several quinoid structures [36l... 

Mizukawa, K., Mncent, S. R., McGeer, P. L., and McGeer, E. G. (1990) Distribution of reduced-nicotinamide-adenine-dmucleotide-phosphate diaphorase-positive cells and fibers in the cat central nervous system. J. Comp. Neurol. 279,281-311... 

The hydroxyl radicals react with the SAMs and locally change the chemical and physical properties of the monolayer surface. Diaphorase patterns are then formed on the substrates by physical adsorption onto the hydrophobic area or by chemical linkage to the hydroxyl radical-attacked area (Figure 12.30). Diaphorase activity can be visualized using SECM by detecting the diaphorase-catalyzed current of feirocenylmethanol coupled with the oxidation of reduced nicotinamide adenine dinucleotide (135). The size of the hydroxyl-radical-attacked area, which determines the resolution of the enzyme patterns, is affected by different factors, including the tip size, the concentration of Fe +, and the potential pulse period for generation of the hydroxyl radical. 

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