Alcohol dehydrogenase EC

The substrate binding pocket of horse liver alcohol dehydrogenase comprises residues from both subunits (Fig. 26B) [123]. The active site is shown in Fig. 27, with NAD(H) bound, and p-bromobenzyl alcohol bound in a non-productive binding mode. The hydrophobic residues (from both subunits) that line the substrate binding 

The active site of horse liver alcohol dehydrogenase, with bound NAD(H) and a non-productive binding mode of p-bromobenzyl alcohol. The 

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Figure 5. Example of dehydrogenase reactions which can be coupled with the bienzymatic bacterial bioluminescent system. ADH = alcohol dehydrogenase (EC 1.1.1.1), SDH = sorbitol dehydrogenase (EC 1.1.1.14), LDH = lactate dehydrogenase (EC 1.1.1.27), MDH = malate dehydrogenase (EC 1.1.1.37).

This approach was coupled to a system of three NAD+-dependent enzymes comprised of alcohol dehydrogenase (EC 1.1.1.1), aldehyde dehydrogenase (EC 1.2.1.3), and formate dehydrogenase (EC 1.2.1.2) to create an electrode theoretically capable of complete oxidation of methanol to carbon dioxide, as shown in Eigure 5. The anode was, in turn, coupled to a platinum-catalyzed oxygen cathode to produce a complete fuel cell operating at pH 7.5. With no externally applied convection, the cell produced power densities of 0.67 mW/cm at 0.49 V for periods of less than 1 min, before the onset of concentration polarization. 

A major class of enzymes that catalyze oxidation-reduction reactions. This class includes dehydrogenases, reductases, oxygenases, peroxidases, and a few synthases. Examples include alcohol dehydrogenase (EC 1.1.1.1), aldehyde oxidase (EC 1.2.3.1), orotate reductase (EC 1.3.1.14), glutamate synthase (EC 1.4.1.14), NAD(P) transhydrogenase (EC 1.6.1.1), and glutathione peroxidase (EC 1.11.1.9). 

Proteins with the same catalytic property do not always have closely similar structures. Alcohol dehydrogenases (EC 1.1.1.1) from yeast [2] and fruit-flies [3,4], for example, have strikingly different primary structures. 

Ethanol sensors were fabricated using the membrane-bound quinohemoprotein alcohol dehydrogenase (EC 1.1.99.8) from different sources and... 

The accuracy of the microwave-excitation spectrometric method was verified by comparing results from it with those of atomic absorption analysis for readily available metalloenzymes of known zinc stoichiometry. Carboxypeptidase A (EC 3.4.12.2), carbonic anhydrase (EC 4.2.1.1), alcohol dehydrogenase (EC l.l.l.l), and alkaline phosphatase (EC 3.1.3.1) were dialyzed vs. metal-free bufiFers, then diluted with 10 mmol/ L KCl or 1 mmol/L HCl for metal analysis (24). For atomic absorption analysis, at least lOO- xg samples were required, but microwave excitation required only 0.1 fig. Even though 1000-fold less protein was required for microwave excitation analysis, the agreement between the data obtained by the two methods is excellent (Table II). So little of the reverse transcriptase was available to us that we could not use atomic absorption for its analyses. 

Alcohol dehydrogenases EC 1.1.1.1 ADH (ADHIA, IB and 1C, ADH4, ADH5, ADH6 andADH7)... 

Several other syntheses of stereospecifically labeled glycine have been devised, and some of these introduce chirality by reduction of a labeled aldehyde. Thus the pro-R specific horse liver alcohol dehydrogenase (EC 1.1.1.1) reduces the aldehydes 36, or H, to the corresponding (S)-alcohols (64) ... 

NAD -dependent alcohol dehydrogenases (EC 1.1.1.1) are encoded in the C. elegans genome (Fig. 15.1). The list of standard PEDANT queries includes EC numbers, PROSITE patterns, Pfam domains, BLOCKS, and SCOP domains, as well as PIR keywords and PIR superfamilies. Although PEDANT does not allow the users to enter their own queries, the variety of data available at this Web site makes it a convenient entry point into the held of comparahve genome analysis. 

Enzymes with niacin coenzymes in human metabolism (examples of 200 enzymes ). L-Lactate dehydrogenase (EC 1.1.1.27) alcohol dehydrogenase (EC l.l.l.l) glyceraldehyde-phosphate dehydrogenase (EC 1.2.1.12) NADPH-cytochrome-P-450-reductase (EC 1.6.2.4). 

Dinuclaotida fold a characteristic folded protein structure constituting part or all of the structure of four NAD-dependent dehydrogenases, and certain other enzymes, some of which do not bind nucleotides. The D.f. was first identified in the tertiary structures of liver alcohol dehydrogenase (EC l.l.l.l), gly-... 

Scheme 11.29. A representation of the reduction of ethanal (acetaldehyde, CHjCHO) by the enzyme alcohol dehydrogenase (EC l.l.l.l) using the reduced form of nicotinamide adenine dinucleotide (NADH) as cofactor to ethanol (CH3CH2OH). The cofactor is oxidized to NAD. EC numbers and some graphic materials provided in this scheme have been taken with permission from appropriate links in a URL starting with http //www.chem.qmul.ac.uk/ iubmb/enzyme/.

In the same fashion, GTP can be converted to GDP-Man as an intermediate in the recychng of GDP-Fuc (Scheme 12) [36]. This conversion can be accomplished by utilizing GDPMP from dried yeast cells and GDP-Fuc-generating enzymes partially purified from the bacterium Klebsiella pneumonia. This system must be coupled to an alcohol dehydrogenase (EC 1.1.1.2), which catalyzes the oxidation of 2-propanol to acetone, along with the reduction of NADP+ to NADPH. Alternatively, Fuc-l-P can be biosynthesized from fucose by the action of fucokinase (EC 2.7.1.52) from porcine liver in the presence of ATP (Scheme 13). Reaction of Fuc-l-P with GTP catalyzed by GDP-Fuc pyrophosphorylase (EC 2.7.7.30) then affords GDP-Fuc [37]. Both of these methods have been utilized in the synthesis of sLe from 3 -SLN. 

Racemic 3-hydroxy[3- C]butyric acid was resolved using the stereospecific 3-hydro-xybutyrate dehydrogenase enzyme (EC 1.1.1.30) which converted the undesired (R)-isomer to [3- " C]acetoacetic acid the latter was decarboxylated in situ by addition of perchloric acid and heating. Subsequent purification of the unreacted (5)-( + )-enantiomer by preparative TLC on silica gel gave a yield of 32.5% in 98% purity. This procedure was an improvement over a previous method that required the addition of acetaldehyde and alcohol dehydrogenase (EC 1.1.1.1) to the reaction mixture to force the equilibrium redox reaction to completion. ... 

Glucose oxidase [EC 1.1.3.4] (grade II, 113 unit-mg"was purchased from Toyobo Co. Alcohol dehydrogenase [EC 1.1.1.1] (grade III,... 

Pyruvate decarboxylase (EC 4.1.1.1) has been characterized in different sources including yeast, bacteria, wheat, maize, sweet potato, and plants [8]. This is the first enzyme of the branch of the glycolytic pathway, which under anaerobic conditions leads to nonoxidative decarboxylation of pyruvate to reduced end-products [9]. In the case of yeast, pyruvate decarboxylase together with alcohol dehydrogenase (EC 1.1.1.1) converts pyruvate to ethanol. 

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