Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:1.1.1.1 (alcohol dehydrogenase)
9,284 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The fusel alcohols 3-methyl-1-butanol, 2-methyl-1-butanol, and 2-methyl-propanol are important flavor compounds in yeast-derived food products and beverages. The formation of these compounds from branched-chain amino acids is generally assumed to occur via the Ehrlich pathway, which involves the concerted action of a branched-chain transaminase, a decarboxylase, and an alcohol dehydrogenase. Partially purified preparations of pyruvate decarboxylase (EC 4.1.1.1) have been reported to catalyze the decarboxylation of the branched-chain 2-oxo acids formed upon transamination of leucine, isoleucine, and valine. Indeed, in a coupled enzymatic assay with horse liver alcohol dehydrogenase, cell extracts of a wild-type Saccharomyces cerevisiae strain exhibited significant decarboxylation rates with these branched-chain 2-oxo acids. Decarboxylation of branched-chain 2-oxo acids was not detectable in cell extracts of an isogenic strain in which all three PDC genes had been disrupted. Experiments with cell extracts from S. cerevisiae mutants expressing a single PDC gene demonstrated that both PDC1- and PDC5-encoded isoenzymes can decarboxylate branched-chain 2-oxo acids. To investigate whether pyruvate decarboxylase is essential for fusel alcohol production by whole cells, wild-type S. cerevisiae and an isogenic pyruvate decarboxylase-negative strain were grown on ethanol with a mixture of leucine, isoleucine, and valine as the nitrogen source. Surprisingly, the three corresponding fusel alcohols were produced in both strains. This result proves that decarboxylation of branched-chain 2-oxo acids via pyruvate decarboxylase is not an essential step in fusel alcohol production.
...
PMID:Pyruvate decarboxylase catalyzes decarboxylation of branched-chain 2-oxo acids but is not essential for fusel alcohol production by Saccharomyces cerevisiae. 954 64

Previous studies have shown an unexpectedly high nutrient requirement for efficient ethanol production by ethanologenic recombinants of Escherichia coli B such as LY01 which contain chromosomally integrated Zymomonas mobilis genes (pdc,adhB) encoding the ethanol pathway. The basis for this requirement has been identified as a media-dependent effect on the expression of the Z. mobilis genes rather than a nutritional limitation. Ethanol production was substantially increased without additional nutrients simply by increasing the level of pyruvate decarboxylase activity. This was accomplished by adding a multicopy plasmid containing pdc alone (but not adhB alone) to strain LY01, and by adding multicopy plasmids which express pdc and adhB from strong promoters. New strong promoters were isolated from random fragments of Z. mobilis DNA and characterized but were not used to construct integrated biocatalysts. These promoters contained regions resembling recognition sites for 3 different E. coli sigma factors: sigma(70), sigma(38), and sigma(28). The most effective plasmid-based promoters for fermentation were recognized by multiple sigma factors, expressed both pdc and adhB at high levels, and produced ethanol efficiently while allowing up to 80% reduction in complex nutrients as compared to LY01. The ability to utilize multiple sigma factors may be advantageous to maintain the high levels of PDC and ADH needed for efficient ethanol production throughout batch fermentation. From this work, we propose that the activation of biosynthetic genes in nutrient-poor media creates a biosynthetic burden that reduces the expression of chromosomal pdc and adhB by competing for transcriptional and translational machinery. This reduced expression can be viewed as analogous to the effect of plasmids (plasmid burden) on the expression of native chromosomal genes.
...
PMID:Biosynthetic burden and plasmid burden limit expression of chromosomally integrated heterologous genes (pdc, adhB) in Escherichia coli. 1051 59

Alterations in gene expression during early stages of dormancy release in grapevine buds were analyzed to facilitate the identification of gene products that may mediate the signal transduction of a dormancy-release signal, or derepression of meristematic activity. In the present report we describe the identification of GDBRPK, a transcript for an SNF-like protein kinase that is up-regulated upon chemical induction of dormancy release by hydrogen cyanamide (HC). Since SNF and SNF-like protein kinases are known as sensors of stress signals, we hypothesize that GDBRPK may be involved in the perception of a stress signal induced by HC. We also describe a simultaneous and remarkable induction of both PDC and ADH transcripts that was observed shortly after HC application, and was of a transient nature. These data may imply that HC application leads to a transient respiratory stress, which likely results in a temporary increase in the AMP/ATP ratio. Since AMP is known as a stress signal that is sensed by SNF-like kinases, we suggest that the SNF-like GDBRPK could serve as the sensor of this signal.
...
PMID:The transduction of the signal for grape bud dormancy breaking induced by hydrogen cyanamide may involve the SNF-like protein kinase GDBRPK. 1105

Hyperhydricity is considered as a physiological disorder that can be induced by different stressing conditions. In the present work we have studied the metabolic and energetic states of hyperhydric carnation shoots. We have evaluated the hypothesis that hypoxia stress is the main factor affecting the metabolism of hyperhydric leaves. Our results indicate a low level of ATP in hyperhydric tissues, but only slight modifications in pyridine nucleotide contents. Concurrently, the glucose-6-phosphate dehydrogenase (G-6-PDH; EC 1.1.1.49) activity in hyperhydric leaves was increased but glucokinase (GK; EC 2.7.1.2) activity was unchanged. We have observed that the metabolism of pyruvate was altered in hyperhydric tissues by the induction of pyruvate synthesis via NADP-dependent malic enzyme (EC 1.1.1.40). The enzymes of the fermentative metabolism pyruvate decarboxylase (PDC; EC 4.1.1.1) and alcohol dehydrogenase (ADH; EC 1.1.1.1) were highly increased in hyperhydric leaves. Sucrose metabolism was modified in hyperhydric leaves with a high increase in the activity of both synthesis and catabolic enzymes. The analysis of the sucrose, glucose and fructose contents indicated that all of these sugars were accumulated in hyperhydric leaves. However, the pinitol content was drastically decreased in hyperhydric leaves. We consider that these results suggest that hyperhydric leaves of carnation have adapted to hypoxia stress conditions by the induction of the oxidative pentose phosphate and fermentative pathways.
...
PMID:Reducing properties, energy efficiency and carbohydrate metabolism in hyperhydric and normal carnation shoots cultured in vitro: a hypoxia stress? 1597 13

The inhibition of branched-chain amino acid (BCAA) biosynthesis was evaluated in pea plants in relation to the ability for induction of fermentative metabolism under aerobic conditions. Chlorsulfuron and imazethapyr (inhibitors of acetolactate synthase, ALS, EC 4.1.3.18) produced a strong induction of pyruvate decarboxylase (PDC, EC 4.1.1.1) and alcohol dehydrogenase (ADH, EC 1.1.1.1) activities and a lesser induction of lactate dehydrogenase (LDH, EC 1.1.1.27) and alanine aminotransferase (AlaAT, EC 2.6.1.2) activities in roots. Inhibition of the second enzyme of the BCAA biosynthesis (ketol-acid reductoisomerase, KARI, EC 1.1.1.86) by Hoe 704 (2-dimethylphosphinoyl-2-hydroxyacetic acid) and CPCA (1,1-cyclopropanedicarboxylic acid) enhanced fermentative enzyme activities including PDC, ADH, and AlaAT. Fermentative metabolism induction occurring with ALS- and KARI-inhibitors was related to a higher expression of PDC. In the case of KARI inhibition, it is proposed that fermentation induction is due to an inhibition of ALS activity resulted from an increase in acetolactate concentration. Fermentative metabolism induction in roots, or at least ethanolic fermentation, appeared to be a general physiological response to the BCAA biosynthesis inhibition.
...
PMID:Fermentative metabolism is induced by inhibiting different enzymes of the branched-chain amino acid biosynthesis pathway in pea plants. 1615 77

Pyruvate decarboxylase (PDC, EC 4.1.1.1) and alcohol dehydrogenase (ADH, EC 1.1.1.1) are responsible for the anaerobic production of acetaldehyde and ethanol in higher plants. In developing soybean embryos, ADH activity increased upon imbibition and then declined exponentially with development, and was undetectable in leaves by 30 days after imbibition. PDC was not detectable in soybean leaves. In contrast, ADH activity remained high in developing cottonwood seedlings, with no decline in activity during development. ADH activity in the first fully expanded leaf of cottonwood was 230 micromoles NADH oxidized per minute per gram dry weight, and increased with leaf age. Maximal PDC activity of cottonwood leaves was 10 micromoles NADH oxidized per minute per gram dry weight. ADH activity in cottonwood roots was induced by anaerobic stress, increasing from 58 to 205 micromoles NADH oxidized per minute per gram dry weight in intact plants in 48 hours, and from 38 to 246 micromoles NADH oxidized per minute per gram dry weight in detached roots in 48 hours. Leaf ADH activity increased by 10 to 20% on exposure to anaerobic conditions. Crude leaf enzyme extracts with high ADH activity reduced little or no NADH when other aldehydes, such as trans-2-hexenal, were provided as substrate. ADH and PDC are constitutive enzyme in cottonwood leaves, but their metabolic role is not known.
...
PMID:Alcohol Dehydrogenase and Pyruvate Decarboxylase Activity in Leaves and Roots of Eastern Cottonwood (Populus deltoides Bartr.) and Soybean (Glycine max L.). 1666 86

Rice seedlings (Oryza sativa L.) were incubated at 5-30 degrees C for 48 h and the effect of temperature on ethanolic fermentation in the seedlings was investigated in terms of low-temperature adaptation. Activities of alcohol dehydrogenase (ADH, EC 1.1.1.1) and pyruvate decarboxylase (PDC, EC 4.1.1.1) in roots and shoots of the seedlings were low at temperatures of 20-30 degrees C, whereas temperatures of 5, 7.5 and 10 degrees C significantly increased ADH and PDC activities in the roots and shoots. Temperatures of 5-10 degrees C also increased ethanol concentrations in the roots and shoots. The ethanol concentrations in the roots and shoots at 7.5 degrees C were 16- and 12-times greater than those in the roots and shoots at 25 degrees C, respectively. These results indicate that low temperatures (5-10 degrees C) induced ethanolic fermentation in the roots and shoots of the seedlings. Ethanol is known to prevent lipid degradation in plant membrane, and increased membrane-lipid fluidization. In addition, an ADH inhibitor, 4-methylpyrazole, decreased low-temperature tolerance in roots and shoots of rice seedlings and this reduction in the tolerance was recovered by exogenous applied ethanol. Therefore, production of ethanol by ethanolic fermentation may lead to low-temperature adaptation in rice plants by altering the physical properties of membrane lipids.
...
PMID:Effect of low temperature on ethanolic fermentation in rice seedlings. 1690 82

We amplified, sequenced and studied the transcriptional regulation of genes of the alcoholic fermentation pathway in the biocontrol and non-Saccharomyces wine yeast, Pichia anomala. Two ADH isogenes, PaADH1 and PaADH2, and one PDC gene, PaPDC1, were amplified from genomic P. anomala DNA by a two-step PCR approach, using degenerated primers against conserved regions of the respective genes for cloning core regions, and PCR-based gene walking for cloning the respective 5' and 3'-ends. According to sequence analysis, ADH1 and PDC1 are most likely cytoplasmatic proteins, while ADH2 is most probably localized in the mitochondria. PaADH1 was expressed during aerobic growth on glucose, ethanol and succinate, but was nine-fold upregulated in response to oxygen limitation when grown on glucose. The gene seems to be involved in both production and consumption of ethanol. Only low expression of PaADH2 was detected during growth on glucose and ethanol, but it was highly expressed during growth on the non-fermentable carbon source succinate and repressed by the addition of glucose. PaPDC1 was expressed during aerobic growth on glucose and was upregulated four-fold in response to oxygen limitation. PaPDC1 expression was lower in cells grown on ethanol and succinate than on glucose and was up- regulated two- and four-fold, respectively, after glucose addition. Our results demonstrate that transcription of genes of the fermentative pathway is regulated by hypoxia and carbon source but posttranscriptional regulation may play a major role in regulating the metabolic flux.
...
PMID:Oxygen and carbon source-regulated expression of PDC and ADH genes in the respiratory yeast Pichia anomala. 1713 21

Metabolome has become an important part of Systems Biology, and a large set of data has already gained by applying the methods of metabolome. How to deal with the data and how to combine data of metabolome with data of other omics are problems that can not be ignored. An Enzyme Amount Multiple Factor was imported into the enzyme kinetic equation. When the enzyme amount in the system changed, in silico model, it means to alter the Enzyme Amount Multiple Factor. In order to observe ethanol concentration response to enzyme amount changes in S. cerevisiae glycolysis pathway model, enzyme amount was separately set at high and low level, the corresponding Enzyme Amount Multiple Factor value was 10 and 0.1, relatively. Based on the result of simulation, twelve enzymes in pathway were separated into two classes, class I and class II by cluster analysis. The four enzymes belonging to class I, ADH, HK, PFK and PDC, all catalyze irreversible reactions. The six out of eight enzymes belonging to class II, ALD, GAPDH, GlcTrans, lpPEP, PGI and TIM, catalyze reversible reactions. The other two enzymes belonging to class II, lpGlyc and PK, catalyze irreversible reactions. Based on this method, data of metabolome and proteomics are easily integrated to accomplish relatively overall analysis of system properties.
...
PMID:[Simulation and analysis of ethanol concentration response to enzyme amount changes in Saccharomyces cerevisiae glycolysis pathway model]. 1746 Sep 12

Wild-type Bacillus subtilis ferments 20 g/liter glucose in 48 h, producing lactate and butanediol, but not ethanol or acetate. To construct an ethanologenic B. subtilis strain, homologous recombination was used to disrupt the native lactate dehydrogenase (LDH) gene (ldh) by chromosomal insertion of the Zymomonas mobilis pyruvate decarboxylase gene (pdc) and alcohol dehydrogenase II gene (adhB) under the control of the ldh native promoter. The values of the intracellular PDC and ADHII enzymatic activities of the engineered B. subtilis BS35 strain were similar to those found in an ethanologenic Escherichia coli strain. BS35 produced ethanol and butanediol; however, the cell growth and glucose consumption rates were reduced by 70 and 65%, respectively, in comparison to those in the progenitor strain. To eliminate butanediol production, the acetolactate synthase gene (alsS) was inactivated. In the BS36 strain (BS35 delta alsS), ethanol production was enhanced, with a high yield (89% of the theoretical); however, the cell growth and glucose consumption rates remained low. Interestingly, kinetic characterization of LDH from B. subtilis showed that it is able to oxidize NADH and NADPH. The expression of the transhydrogenase encoded by udhA from E. coli allowed a partial recovery of the cell growth rate and an early onset of ethanol production. Beyond pyruvate-to-lactate conversion and NADH oxidation, an additional key physiological role of LDH for glucose consumption under fermentative conditions is suggested. Long-term cultivation showed that 8.9 g/liter of ethanol can be obtained using strain BS37 (BS35 delta alsS udhA+). As far as we know, this is the highest ethanol titer and yield reported with a B. subtilis strain.
...
PMID:Metabolic engineering of Bacillus subtilis for ethanol production: lactate dehydrogenase plays a key role in fermentative metabolism. 1758 70


1 2 Next >>

---