Alcohol-dehydrogenase-nicotinamide

J. Wang, E. Gonzalez-Romero and M. Ozsoz, Renewable alcohol biosensors based on alcohol-dehydrogenase/nicotinamide-adenine-dinucleotide graphite epoxy electrodes, Electroanalysis, 4 (1992) 539-544. 

The substrate models concerned were fitted into the model of the active site of alcohol dehydrogenase-nicotinamide adenine dinucleotide (ADH-NAD) with VDW contacts, etc. not considered explicitly. 

Jagodzinski, P. W., Petlcolas, W. L. (1981) Resonance Enhanced Raman Identification of the Zinc-Oxygen Bond in a Horse Liver Alcohol Dehydrogenase-Nicotinamide Adenine Dinucleotide-Aldehyde Transient Chemical Intermediate, J. Am. Chem. Soc. 103, 234-236. 

Jagodzinski PW, Peticolas WL (1981) Resonance enhanced Raman identification of the zinc-oxygen bond in a horse liver alcohol dehydrogenase-nicotinamide adenine dinucleotide-aldehyde transient chemical intermediate. J Am Chem Soc 103 234-236 Jakovac IJ, Goodbrand HB, Lok KP, Jones JB (1982) Enzymes in organic synthesis. 24. Preparations of enantiomerically pure chiral lactones via stereospecific horse liver alcohol dehydrogenase... 

Figure 1.9 Examples of functionally important intrinsic metal atoms in proteins, (a) The di-iron center of the enzyme ribonucleotide reductase. Two iron atoms form a redox center that produces a free radical in a nearby tyrosine side chain. The iron atoms are bridged by a glutamic acid residue and a negatively charged oxygen atom called a p-oxo bridge. The coordination of the iron atoms is completed by histidine, aspartic acid, and glutamic acid side chains as well as water molecules, (b) The catalytically active zinc atom in the enzyme alcohol dehydrogenase. The zinc atom is coordinated to the protein by one histidine and two cysteine side chains. During catalysis zinc binds an alcohol molecule in a suitable position for hydride transfer to the coenzyme moiety, a nicotinamide, [(a) Adapted from P. Nordlund et al., Nature 345 593-598, 1990.)...

Cu-+ Peroxidase Cytochrome oxidase Nicotinamide adenine dinucleotide (NAD) Hydride ion (H ) Alcohol dehydrogenase... 

The leading substrate (A) is nicotinamide adenine dinucleotide (NAD ), and NAD and NADH (product Q) compete for a common site on E. A specific example is offered by alcohol dehydrogenase (ADH) ... 

NAD (P) " -dependent enzymes are stereospecific. Malate dehydrogenase, for example, transfers a hydride to die pro-/ position of NADH, whereas glyceraldehyde-3-phosphate dehydrogenase transfers a hydride to die pro-5 position of the nicotinamide. Alcohol dehydrogenase removes a hydride from the pro-i position of edianol and transfers it to die pro-i position of NADH. 

Ethanol Electrodes The reliable sensing of ethanol is of great significance in various disciplines. The enzymatic reaction of ethanol with the cofactor nicotinamide-adenine dinucleotide (NAD+), in the presence of alcohol dehydrogenase (ADH)... 

Ethanol is oxidized by alcohol dehydrogenase (in the presence of nicotinamide adenine dinucleotide [NAD]) or the microsomal ethanol oxidizing system (MEOS) (in the presence of reduced nicotinamide adenine dinucleotide phosphate [NADPH]). Acetaldehyde, the first product in ethanol oxidation, is metabolized to acetic acid by aldehyde dehydrogenase in the presence of NAD. Acetic acid is broken down through the citric acid cycle to carbon dioxide (CO2) and water (H2O). Impairment of the metabolism of acetaldehyde to acetic acid is the major mechanism of action of disulfiram for the treatment of alcoholism. 

Zinc-containing alcohol dehydrogenases take up two electrons and a proton from alcohols in the form of a hydride. The hydride acceptor is usually NAD(P) (the oxidized form of nicotinamide adenine dinucleotide (NADH) or its phosphorylated derivative, NADPH). Several liver alcohol dehydrogenases have been structurally characterized, and Pig. 17.8 shows the environment around the catalytic Zn center and the bound NADH cofactor. 

US5846813 [48] desulfurization of DBT by Rhodococcus Sp. IGTS8. biodesulfurization of a fossil fuel by adding to the biocatalytic aqueous phase a nicotinamide adenosine dinucleotide and an additional amount of a group III alcohol dehydrogenase. Incubation and separation follows the mixing step. 

An isolated DNA molecule comprising DNA which encodes a group III alcohol dehydrogenase and DNA which encodes a BDS-active biocatalyst via nicotinamide adenosine dinucleotide-dependent manner. 

When the enzyme alcohol dehydrogenase converts acetaldehyde to ethanol, NADH acts as a reducing agent by transferring a hydride from C4 of the nicotinamide ring to the carbonyl group of acetaldehyde. 

Nicotinamide Adenine Dinucleotide (NAD+) Alcohol dehydrogenase, Lactate oxidase... 

Nicotinamide Adenine Dinucleotide phosphate (NADP+) Glutamate dehydrogenase, Alcohol dehydrogenase, Aryl-aldehyde dehydrogenase... 

In the classical procedures W, the 5-T or D-labeled mevalonate is converted enzymatically to farnesol, which is then oxidized to famesal by liver alcohol dehydrogenase. This enzyme transfers the pro-R hydrogen of C—1 of ethanol or geraniol (or farnesol) to the 4 pro R position of the nicotinamide ring of NAD. 

A. Gafni and L. Brand, Fluorescence decay studies of reduced nicotinamide adenine dinucleotide in solution and bound to liver alcohol dehydrogenase, Biochemistry 15, 3165-3171 (1976). 

Figure 6.1 Pathways involved in glucose oxidation by plant cells (a) glycolysis, (b) Krebs cycle, (c) mitochondrial cytochrome chain. Under anoxic conditions. Reactions 1, 2 and 3 of glycolysis are catalysed by lactate dehydrogenase, pyruvate decarboxylase and alcohol dehydrogenase, respectively. ATP and ADP, adenosine tri- and diphosphate NAD and NADHa, oxidized and reduced forms of nicotinamide adenine dinucleotide PGA, phosphoglyceraldehyde PEP, phosphoenolpyruvate Acetyl-CoA, acetyl coenzyme A FP, flavoprotein cyt, cytochrome e, electron. (Modified from Fitter and Hay, 2002). Reprinted with permission from Elsevier...

NAD is one of Nature s most important oxidizing agents it can be considered as a biological equivalent of the chromium(VI) ion. NAD is shorthand for nicotinamide adenine dinucleotide it is a co-enzyme, which together with an enzyme is essential for several life-sustaining processes (Box 2.2). On reduction it forms the corresponding 1,4-dihydropyridine, NADH, The oxidation of ethanol to acetaldehyde (ethanal) is effected by the enzyme alcohol dehydrogenase and mediated by NAD (Scheme 2.31). 

ADH, alcohol dehydrogenase CYP, cytochrome P450 NAD, nicotinamide-adenme dinucleotide NADPH, nicotmamide-adenine dinucleotide phosphate (reduced form)... 

Although zinc itself is not redox-active, some class I enzymes containing zinc in their active sites are known. The most prominent are probably alcohol dehydrogenase and copper-zinc superoxide dismutase (Cu,Zn-SOD). AU have in common that the redox-active agent is another transition-metal ion (copper in Cu,Zn-SOD) or a cofactor such as nicotinamide adenine dinucleotide (NAD+/NADH). The Zn(II) ion affects the redox reaction only in an indirect manner, but is nevCTtheless essential and cannot be regarded simply as a structural factor. 

Alcohol dehydrogenases (ADH EC 1.1.1.1), for which several X-ray structures are available ", catalyze the biological oxidation of primary and secondary alcohols via the formal transfer of a hydride anion to the oxidized form of nicotinamide adenine dinucleotide (NAD ), coupled with the release of a proton. Liver alcohol dehydrogenase (LADH) consists of two similar subunits, each of which contains two zinc sites, but only one site within each subunit is catalytically active. The catalytic zinc is coordinated in a distorted tetrahedral manner to a histidine residue, two cysteine residues and a water molecule. The remaining zinc is coordinated tetrahedrally to four cysteine residues and plays only a structural role . 

Metabolism of ethanol by alcohol dehydrogenase and the microsomal ethanol-oxidizing system (MEOS). Alcohol dehydrogenase and aldehyde dehydrogenase are inhibited by fomepizole and disulfiram, respectively. NAD +, nicotinamide adenine dinucleotide NADPH, nicotinamide adenine dinucleotide phosphate. 

However, this glycine-rich segment has other functions in short-chain alcohol dehydrogenases. Tanaka et al. [37] and our 3D modeling [60] indicate that this glycine rich segment has an important role in cofactor specificity and binding of the nicotinamide moiety to 11P-HSD. 

Biological Reduction by Alcohol Dehydrogenases. Bioreductions of atoms doubly bound to oxygen are consistent with a mechanism for attack that would involve a nucleophilic form of hydrogen. Indeed such bioreductants occur in organisms. The reactive portion of one such reductant, the nicotinamide ring of NADH or NADPH (referred to as NAD(P)H), is ... 

Nicotinamide-dependent enzymes operate in a highly stereospecific manner. This phenomenon was first demonstrated for alcohol dehydrogenase which catalyzes the direct and stereospecific transfer of the pro-(R) hydrogen at C-l of ethanol to the re face of NAD+, or, in the reverse direction, the pro-(R) hydrogen of NADH to the re face of acetaldehyde (equation 2) (B-71MI11001, B-79MI11000). Many other nicotinamide-dependent... 

Ethanol also may be determined using alcohol dehydrogenase and measuring the change in nicotinamide adenine dinucleotide (NAD+) to the reduced form (NADH) at 340 nm. 

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