Thionicotinamide adenine dinucleotide

Thionicotinamide adenine dinucleotide glyceraldehyde-3-phosphate dehydrogenase and, 30... 

D-Glucitol dehydrogenase has broad substrate-specificity. The enzyme oxidizes D-glucitol, L-iditol, ribitol, and xylitol in the presence of NAD+ cofactor.414 424 NAD+ can be replaced by 3-acetylpyridine adenine dinucleotide (AcPyAD), 3-thionicotinamide adenine dinucleotide (TNAD), or nicotinamide hypoxanthine dinucleotide (NHD).414... 

When Rudolph and Fromm used thionicotinamide adenine dinucleotide (thio-DPN) as an alternate substrate for NAD+ and varied the concentration of ethanol with liver alcohol dehydrogenase [following the reaction at 342 nm, the isosbes-tic point for thio-DPN and reduced thio-DPN (thio-DPNH)], they saw what appeared to be concave upward reciprocal plots with partial substrate inhibition in the presence of thio-DPN (38). However, the asymptote intercepts appeared to decrease with increased thio-DPN concentration, which is not what the above equations predict for a case where a minimum is present in the curve. There must have been other interactions that caused the substrate inhibition by ethanol in the presence of thio-DPN. 

Nicotinamide (34) and structurally related 51 compounds were subjected to the halting activity bioassay to elucidate the structure-activity relationships [105]. The highest activity was recorded in thionicotinamide (35) followed by pyrazinamide (36) and nicotinamide (34). Nicotinamide adenine dinucleotide (NAD) (oxidized form), nicotinamide adenine dinucleotide phosphate (NADP) (oxidized form), (3-nicotinamide mononucleotide (oxidized form) showed halting activity at ca. 10"7 M... 

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