Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.1.1.1 (alcohol dehydrogenase)
 9,284 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Two isoenzymes of an NADP+ -dependent cinnamyl alcohol dehydrogenase and an NAD+ - dependent aliphatic alcohol dehydrogenase were extracted from cell suspension cultures of soybean (Glycine max L., var. Mandarin) which form lignin during growth. These enzymes could be separated from each other by chromatography on DEAE-cellulose and hydroxyapatite. The cinnamyl alcohol dehydrogenase isoenzymes were partially purified by (NH4)2SO4 fractionation, and column chromatography on DEAE-cellulose, Sephadex G-100, and hydroxyapatite. The molecular weight of the enzymes were estimated by the elution volumes from a Sephadex G-100 column and were found to be about 43,000 (isoenzyme 1) and 69,000 (isoenzyme 2). Maximum rates of reaction were observed in the case of coniferyl alcohol oxidation at pH 9.2 (Isoenzyme 1) and pH 8.8 (isoenzyme 2); in the reverse reaction pH 6.5 was optimal for isoenzyme 2. Whereas isoenzyme 1 is specific for coniferyl alcohol, isoenzyme 2 can also oxidize cinnamyl alcohol and a number of substituted cinnamyl alcohols, Km values for substituted cinnamaldehydes are 3-11 times lower than for the corresponding alcohols. Neither isoenzyme reacted with benzyl alcohol, anisic alcohol or ethanol. Substrate inhibition for the forward and reverse reaction was found with isoenzyme 2 but not with isoenzyme 1. The equilibrium constant was determined to be about 10(9) in favour of coniferaldehyde reduction. The possible role of the cinnamyl alcohol dehydrogenase in lignin biosynthesis is discussed.
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PMID:Purification and properties of isoenzymes of cinnamyl-alcohol dehydrogenase from soybean-cell-suspension cultures. 3031 43

A comparative study of cell cytosol alcohol dehydrogenase (ADH) from yeast Torulopsis candida IBFM-Y-127 grown on glucose and hexadecane which were the only source of carbon, was made. In both cases ADH had a pH optimum within the range of 7.0--10.0, when various normal primary alcohols (C2--C16) were used. The enzyme was active only in the presence of NAD, which cannot be substituted by NADP. The total activity of ADH decreased approximately 8-fold when the length of hydrocarbon radicals was changed from C2 up to C16. When the cells were grown on hexadecane, only ethyl, n-buthyl, n-amyl and n-hexyl alcohols were active as substrates. The dehydration rate of each alcohol was far lower than that for the cytosol of glucose-grown cells. In the latter case the enzyme activity also decreased with an increase in the alcohol radical from C2 to C6. In all cases studied methyl alcohol and cyclic (cinnamyl alcohol--C8) alcohol were not dehydrated at all. Disc-electrophoresis in polyacrylamide gel, involving gel colouration for the assay of enzyme activity showed that glucose--grown cell cytosol contained three forms of ADH. One of those forms was highly active when short--chain normal primary alcohols were used; this form may be probably regarded as "classical" ADH (EC 1.1.1.1). The two other forms caused intensive dehydration of long-chain alcohols (the best substrates were C7--C10 alcohols for one form and C10--C14 for the others). The two forms of ADH are probably isoenzymes of octanol dehydrogenase (EC 1.1.1.73). Cytosol of cells grown on n-alcane, had a reduced number of ADH forms. The data obtained are discussed in terms of the regulatory role of carbon and energy source (glucose or hexadecane) in the redistribution of alcohol dehydrogenases between structural components of cells (mitochondria) and cytosol.
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PMID:[Cytosolic alcohol dehydrogenases from yeast Torulopsis candida]. 1 29

One of the promises held out by protein engineering is the ability to alter predictably the properties of an enzyme to enable it to find new substrates or catalyse existing substrates more efficiently, such manipulations being of interest both enzymologically and, potentially, industrially. It has been postulated that in yeast alcohol dehydrogenase (YADH-1) certain amino acids such as Trp 93 and Thr 48 constrict the active site due to their bulky side chains and thus impede catalysis of molecules larger than ethanol. To study effects of enlarging the active site we have made two changes into YADH-1, replacing Trp 93 with Phe and Thr 48 with Ser. Kinetic experiments showed that this enzyme had marked increases in reaction velocity for the n-alcohols propanol, butanol, pentanol, hexanol, heptanol, octanol and cinnamyl alcohol compared to the parent, agreeing with the prediction that expanding the active site should facilitate the oxidation of larger alcohols. The substrate affinities were slightly reduced in the altered enzyme, possibly due to its having reduced hydrophobicity at Phe 93.
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PMID:Protein engineering of alcohol dehydrogenase--1. Effects of two amino acid changes in the active site of yeast ADH-1. 333 42

The activity and the kinetic properties of horse liver alcohol dehydrogenase have been studied in water-in-oil microemulsions containing sodium dodecyl sulfate (SDS) or hexadecyl trimethylammonium bromide (CTAB), 1-butanol or 1-pentanol or 1-hexanol or t-butanol, water and cyclohexane alone or with octane. In the anionic microemulsions (i.e. containing sodium dodecyl sulfate), the enzyme quickly lost its activity, but was efficiently protected by the coenzyme and some adenine nucleotides. In the cationic microemulsions (i.e. containing hexadecyl trimethylammonium bromide), the enzyme activity was more stable and with higher alcohols was stable for at least 20 min. The Michaelis constant of NAD+ calculated with respect to the water content was nearly constant and higher than in water. The maximum velocity in anionic microemulsions depends on the water content whereas in cationic microemulsions, the maximum velocity did not show a clear dependence on the water content and was close to the maximum velocity found in water. The pH dependence of Km and Vmax in these microemulsions was similar to that observed in water. The kinetic data for a hydrophobic substrate, cinnamyl alcohol, showed that this alcohol partitions between the pseudo-phases and thus the apparent Michaelis constant and the concentration at which substrate-excess inhibition appeared were increased. The catalytic properties of the enzyme in microemulsions were illustrated by the preparative reduction of cinnamaldehyde with cofactor recycling. The rate determination of NAD+ reduction and of 1-butanol/cinnamaldehyde redox reaction showed that at low water content (2.8%), the NAD+ reduction rate was close to zero whereas the redox reaction rate was about half of the rate at higher water content. Probably at low water content the coenzyme binding-dissociation rates are reduced much more than the binding-dissociation rates of the substrates and the rates of the ternary complex interconversion. The cationic microemulsions seemed to be very favorable medium for enzyme activity, the tetraalkyl ammonium surfactant causing less denaturation than the anionic detergent dodecyl sulfate.
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PMID:Enzymes and microemulsions. Activity and kinetic properties of liver alcohol dehydrogenase in ionic water-in-oil microemulsions. 383 Jan 76

The geometric specificity of three different alcohol dehydrogenases (alcohol:NAD+ oxidoreductase, EC 1.1.1.1) (from yeast, from horse liver, and from Leuconostoc mesenteroides) in the reduction of trans- and cis-cinnamaldehydes has been investigated. All three enzymes display a remarkable trans specificity: they react with the trans isomer 7 to 647 times faster than with its cis counterpart. Experiments with the enzymatic reduction of 3-phenylpropionaldehyde, a saturated analog of cinnamaldehyde, have revealed that whereas trans-cinnamaldehyde possesses the "right" configuration for the active centers of the alcohol dehydrogenases, the cis isomer apparently does not fit the active centers well. All three alcohol dehydrogenases studied also exhibit a marked trans specificity in the reaction with alpha-methylcinnamaldehyde. The geometric specificity of alcohol dehydrogenases can be used for the production of otherwise hard to synthesize cis isomers of unsaturated aldehydes from their readily available trans counterparts: trans-cinnamaldehyde was irradiated with ultraviolet light (which converted it to a mixture of trans and cis isomers) then treated with NADH and yeast alcohol dehydrogenase (which selectively reduces only trans aldehyde into the alcohol), and finally the mixture of cis-cinnamaldehyde and trans-cinnamyl alcohol was separated easily by preparative column chromatography.
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PMID:Geometric specificity of alcohol dehydrogenases and its potential for separation of trans and cis isomers of unsaturated aldehydes. 704 6

Rats dosed with cinnamic aldehyde (I) excreted two mercapturic acids in the urine. The major one was identified as N-acetyl-S-(1-phenyl-3-hydroxypropyl)cysteine (V). The minor one was identified as N-acetyl-S-(1-phenyl-2-carboxy ethyl)cysteine (VI). The ratio appeared to be V : VI = 4 : 1. The hydroxy mercapturic acid (V) was also isolated from urine of rats dosed with cinnamyl alcohol (II). The total mercapturic acid excretion as percentage of the dose was 14.8 +/- 1.9% for cinnamic aldehyde (250 mg/kg) (n = 4) and 8.8 +/- 1.7% for cinnamyl alcohol (n = 4) (125 mg/kg). Inhibition of the alcohol dehydrogenase by pyrazole (206 mg/kg) diminished the thioether excretion of cinnamyl alcohol to 3.3 +/- 1.4% of the dose (n = 8). Cinnamic aldehyde has been proposed to be an intermediate in the mercapturic acid formation of cinnamyl alcohol.
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PMID:Isolation and identification of mercapturic acids of cinnamic aldehyde and cinnamyl alcohol from urine of female rats. 732 1

The inducing effects of ethanol on alcohol dehydrogenase and the key enzymes of the glyoxylate cycle, isocitrate lyase and malate synthase, in Euglena cells were investigated. Ethanol as the sole carbon source resulted in increases in alcohol dehydrogenase and the two glyoxylate cycle enzymes. The experimental results indicated that ethanol is assimilated by alcohol dehydrogenase and the glyoxylate cycle in Euglena. Mitochondria from aerobically grown Euglena contain a unique type of alcohol dehydrogenase that accounts for their ability to respire with ethanol as a substrate. This alcohol dehydrogenase was purified to homogeneity from ethanol-grown Euglena gracilis. The mitochondrial alcohol dehydrogenase was NAD(+)-specific but not NADP(+)-specific. Ethanol was the most active substrate, but the enzyme was also active towards 1-butanol, 1-heptanol, cinnamyl alcohol, and myristyl alcohol. These results indicated that mitochondrial alcohol dehydrogenase participated in alcohol metabolism in Euglena gracilis.
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PMID:Mitochondrial alcohol dehydrogenase from ethanol-grown Euglena gracilis. 749 Feb 57

Analysis of a crystal structure of alcohol dehydrogenase (Adh) from horse liver suggests that Trp54 in the homologous yeast alcohol dehydrogenase prevents the yeast enzyme from efficiently catalysing the oxidation of long-chain primary alcohols with branching at the 4 position (e.g. 4-methyl-1-pentanol, cinnamyl alcohol). This residue has been altered to Leu by site-directed mutagenesis. The alteration yields an enzyme that serves as an effective catalyst for both longer straight-chain primary alcohols and branched chain alcohols.
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PMID:Engineering yeast alcohol dehydrogenase. Replacing Trp54 by Leu broadens substrate specificity. 853 67

We describe an aromatic alcohol dehydrogenase with properties indicating a novel type of function in the defense response of plants to pathogens. To obtain the enzyme free of contamination with possible isoforms, a parsley (Petroselinum crispum) cDNA comprising the entire coding region of the elicitor-responsive gene, ELI3, was expressed in Escherichia coli. In accord with large amino acid sequence similarities with established cinnamyl and benzyl alcohol dehydrogenases from other plants, the enzyme efficiently reduced various cinnamyl and benzyl aldehydes using NADPH as a co-substrate. Highest substrate affinities were observed for cinnamaldehyde, 4-coumaraldehyde and coniferaldehyde, whereas sinapaldehyde, one of the most efficient substrates of several previously analyzed cinnamyl alcohol dehydrogenases and a characteristic precursor molecule of angiosperm lignin, was not converted. A single form of ELI3 mRNA was strongly and rapidly induced in fungal elicitor-treated parsley cells. These results, together with earlier findings that the ELI3 gene is strongly activated both in elicitor-treated parsley cells and at fungal infection sites in parsley leaves, but not in lignifying tissue, suggest a specific role of this enzyme in pathogen defense-related phenylpropanoid metabolism.
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PMID:A novel type of pathogen defense-related cinnamyl alcohol dehydrogenase. 937 88

A previous study of the effect of zinc deprivation on Mycobacterium bovis BCG pointed out the potential importance of an alcohol dehydrogenase for maintaining the hydrophobic character of the cell envelope. In this report, the effect of the overexpression of the M. bovis BCG alcohol dehydrogenase (ADH) in Mycobacterium smegmatis and M. bovis BCG is described. The purification of the enzyme was performed to apparent homogeneity from overexpressing M. bovis BCG cells and its kinetic parameters were determined. The enzyme showed a strong preference for both aromatic and aliphatic aldehydes while the corresponding alcohols were processed 100-1000-fold less efficiently. The best kcat/Km values were found with benzaldehyde > 3-methoxybenzaldehyde > octanal > coniferaldehyde. A phylogenetic analysis clearly revealed that the M. bovis BCG ADH together with the ADHs from Bacillus subtilis and Helicobacter pylori formed a sister group of the class C medium-chain alcohol dehydrogenases, the plant cinnamyl alcohol dehydrogenases (CADs). Comparison of the kinetic properties of our ADH with some related class C enzymes indicated that the mycobacterial enzyme substrate profile resembled that of the CADs involved in plant defence rather than those implicated in lignification. A possible role for the M. bovis BCG ADH in the biosynthesis of the lipids composing the mycobacterial cell envelope is proposed.
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PMID:Overexpression, purification and characterization of Mycobacterium bovis BCG alcohol dehydrogenase. 1033 11


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