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

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Query: EC:3.2.1.26 (invertase)
4,927 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To determine whether jejunoileal bypass operation and alcohol administration exerted a synergistic effect on the activities of brush border membrane enzymes and on liver morphology, adult rats where submitted either to sham operation or to jejunoileal bypass operation. 2 weeks after operation the rats received a 15% solution of ethanol during a period of 4 weeks, controls received water. In the sham-operated rats, alcohol provoked stimulation of the disaccharidase activities in the proximal jejunum but had no effect on these activities in the ileum. Bypass operation alone induced a significant increase in sucrase activity in the functioning ileum but had no effect on the jejunal disaccharidase activities. Alcohol administered after bypass provoked a further increase in ileal brush border sucrase activity. The increase of the brush border enzyme specific activities in the excluded loop resulted from the important protein loss observed in this segment. Alcohol alone or bypass operation by itself had little effect on liver morphology. In contrast, when associated they induced extensive accumulation of fat droplets in the hepatocytes. Since alcohol is frequently associated with the diet in man, alcohol should be considered as an important contributing factor to intestinal enzyme adaptation and liver dysfunction after jejunoileal bypass operation.
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PMID:Effect of chronic alcohol administration on liver morphology and on brush border membrane enzymes after jejunoileal bypass operation in rat. 681 78

Two mutants carrying different deletions of the IMP2 coding sequence of Saccharomyces cerevisiae, delta T1, which encodes a protein lacking the last 26 C-terminal amino acids, and delta T2, which completely lacks the coding region, were analysed for derepression of glucose-repressible maltose, galactose, raffinose and ethanol utilization pathways in response to glucose limitation. The role of the IMP2 gene product in the regulation of carbon catabolite repressible enzymes maltase, invertase, alcohol dehydrogenase, NAD-dependent glutamate dehydrogenase (NAD-GDH) and L-lactate:ferricytochrome-c oxidoreductase (L-LCR) was also analysed. The IMP2 gene product is required for the rapid glucose derepression of all above-mentioned carbon source utilization pathways and of all the enzymes except for L-LCR. NAD-GDH is regulated by IMP2 in the opposite way and, in fact, this enzyme was released at higher levels in both imp2 mutants than in the wild-type strain. Therefore, the product of IMP2 appears to be involved in positive and negative regulation. Both deletions result in growth and catalytic defects; in some cases partial modification of the gene product yielded more dramatic effects than its complete absence. Moreover, evidence is provided that the IMP2 gene product regulates galactose- and maltose-inducible genes at the transcriptional level and is a positive regulator of maltase, maltose permease and galactose permease gene expression.
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PMID:IMP2, a gene involved in the expression of glucose-repressible genes in Saccharomyces cerevisiae. 749 32

Two studies using broiler chicks and one using adult White Leghorn roosters were conducted to determine the influence of stachyose and raffinose (alpha-galactosides of sucrose) present in soybean meal (SBM) on the nutritional value of the meal. In Experiment 1, the addition of four levels (0, .05, .10, or .20 g/kg) of alpha-galactosidase with and without 1 g/kg of invertase to a corn-SBM diet had no effect on weight gain, feed efficiency, protein digestibility, or the digestible energy value of the feed when fed to broiler chicks. However, both enzymes decreased (P < .001) dietary AMEn. In Experiment 2, ethanol extraction and incubation of SBM with alpha-galactosidase decreased the concentrations of the alpha-galactosides of sucrose in SBM from 6.59 to .81 and 1.43%, respectively. However, when broiler chicks were fed semi-purified diets containing SBM, ethanol-extracted SBM, water-incubated SBM, or water plus alpha-galactosidase-incubated SBM, no improvements in weight gain, feed efficiency, or apparent protein digestibility were observed. There was also no improvement in TMEn when the above meals were precision fed to adult White Leghorn roosters (Experiment 3). These results indicate that the removal of up to approximately 90% of the alpha-galactosides of sucrose has no beneficial effect on the nutritional value of SBM for chickens.
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PMID:Removal of the alpha-galactosides of sucrose from soybean meal using either ethanol extraction or exogenous alpha-galactosidase and broiler performance. 750 93

The aim of the study was to ascertain whether the exposure to ethanol of human colon carcinoma CaCo-2 and HT-29 cell lines affects the differentiation process. As an index of enterocytic differentiation, the expression of sucrase, alkaline phosphatase, alpha 2,6-sialyltransferase toward the N-acetyllactosaminic sequence, and beta 1,4-N-acetylgalactosaminyltransferase (beta 1,4GalNAc-transferase) was examined. The latter enzyme is responsible for the biosynthesis of Sda carbohydrate histo-blood antigen, which mainly occurs in human colonic cells; its expression in CaCo-2 cells depends strictly on the enterocytic differentiation. The addition of ethanol in the culture medium resulted in a significant increment of sucrase and alpha 2,6-sialyltransferase activities in both cell lines, as well as the beta 1,4GalNAc-transferase activity in CaCo-2 cells and alkaline phosphatase activity in HT-29 cells. The increment was dose-dependent in the range between 50 and 200 mM ethanol and evident after 2 days of exposure in both cell systems. These results support the notion that, as occurs for cell lines of different origin, the ethanol in vitro positively affects the differentiation of intestinal cells, namely along the enterocytic lineage. The putative mechanism by which ethanol interferes with the maturation process of colonic cells is discussed.
Alcohol Clin Exp Res 1994 Dec
PMID:Effect of ethanol on human colon carcinoma CaCo-2 and HT-29 cell lines during the maturation process. 769 34

The effect of feeding ethanol daily for 40 days was studied on various brush border enzymes in rat intestine. Brush border alkaline phosphatase (AP), lactase, gamma-glutamyltranspeptidase (gamma-GTP), p-nitrophenyl (PNP)-beta-D-galactosidase (P < 0.01) and sucrase (P < 0.001) were significantly enhanced while leucine aminopeptidase and PNP-beta-D-glucosidase activities were unaltered in ethanol fed rats compared to the controls. Kinetic studies revealed that an increase in Vmax together with a decrease in affinity in case of gamma-GTP and an increase in Vmax for AP and sucrase were responsible for the observed stimulation of enzyme activities in ethanol administered rats. Significant changes in enzyme activities were observed in different populations of enterocytes along the crypt-villus unit in the ethanol fed animals. These observations suggest that ethanol feeding modifies the brush border enzymes in rat intestine but the underlying mechanisms seem to be distinct in differentiating enterocytes.
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PMID:Expression of brush border enzymes in ethanol fed rat intestine. 782 69

The expression of gluconeogenic fructose-1,6-bisphosphatase (encoded by the FBP1 gene) depends on the carbon source. Analysis of the FBP1 promoter revealed two upstream activating elements, UAS1FBP1 and UAS2FBP1, which confer carbon source-dependent regulation on a heterologous reporter gene. On glucose media neither element was activated, whereas after transfer to ethanol a 100-fold derepression was observed. This gene activation depended on the previously identified derepression genes CAT1 (SNF1) (encoding a protein kinase) and CAT3 (SNF4) (probably encoding a subunit of Cat1p [Snf1p]). Screening for mutations specifically involved in UAS1FBP1 derepression revealed the new recessive derepression mutation cat8. The cat8 mutants also failed to derepress UAS2FBP1, and these mutants were unable to grow on nonfermentable carbon sources. The CAT8 gene encodes a zinc cluster protein related to Saccharomyces cerevisiae Gal4p. Deletion of CAT8 caused a defect in glucose derepression which affected all key gluconeogenic enzymes. Derepression of glucose-repressible invertase and maltase was still normally regulated. A CAT8-lacZ promoter fusion revealed that the CAT8 gene itself is repressed by Cat4p (Mig1p). These results suggest that gluconeogenic genes are derepressed upon binding of Cat8p, whose synthesis depends on the release of Cat4p (Mig1p) from the CAT8 promoter. However, gluconeogenic promoters are still glucose repressed in cat4 mutants, which indicates that in addition to its transcription, the Cat8p protein needs further activation. The observation that multicopy expression of CAT8 reverses the inability of cat1 and cat3 mutants to grow on ethanol indicates that Cat8p might be the substrate of the Cat1p/Cat3p protein kinase.
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PMID:CAT8, a new zinc cluster-encoding gene necessary for derepression of gluconeogenic enzymes in the yeast Saccharomyces cerevisiae. 789 85

Conidia of certain penicillin producing Penicillium chrysogenum industrial strains produced polyfructose. Two types of polyfructoses were formed by conidia of P. chrysogenum B10 from sucrose and with less yield from raffinose. Ten percent of fructans were in water insoluble form attached to the outer wall of conidia. The other, ethanol precipitable fructan formed a colloid opalescent solution. The latter had inulin type beta (2-->1) bonds--identified by 13C NMR spectroscopy--between fructose molecules and had a molecular weight of 217,000 Daltons. The KM value of sucrose hydrolysis--the first step of inulin production--was 0.86 M. The invertase hydrolysed about 70% of sucrose on the second day. Optimal conditions for inulin formation were: pH 6.0, 25-45 degrees C, 100 mg/ml sucrose, 10(7) spore/ml. The maximum conversion rate of fructose from sucrose into precipitable inulin was about 10% after 48 h incubation. The inulin production could be inhibited by glucose.
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PMID:Inulin formation of penicillin producing industrial Penicillium chrysogenum strains. 797 14

Balance studies utilizing laying hens and adult cockerels were conducted to determine the influence of oligosaccharides (raffinose and stachyose) present in canola meal (CM) on the digestibility of nonstarch polysaccharides (NSP) and on the TMEn of the meal. Ethanol extraction was used to produce oligosaccharide-free meal, and exogenous dietary enzymes (alpha-galactosidase and invertase) were employed to bring about oligosaccharide hydrolysis in the intestinal tract of the birds. In each of two balance trials, six hens individually housed were randomly allotted to each of the experimental diets in completely randomized design. Experiment 1 consisted of a factorial arrangement of treatments (two sources of proteins with or without enzyme supplementation), whereas Experiment 2 consisted of five diets: semipurified CM control, semipurified ethanol-extracted CM; semipurified ethanol-extracted CM plus raffinose; conventional CM; and conventional ethanol-extracted CM. Elimination of oligosaccharides by the use of exogenous dietary enzymes had no effect on NSP digestion. Removal of oligosaccharides by ethanol extraction increased NSP digestibility from 4 to 8%. A more pronounced effect (17% NSP digestion) was noted in hens fed a wheat-based diet containing 30% oligosaccharide-free CM. This latter effect may have been due to the relatively high content of water-soluble polysaccharides contributed by the wheat portion of the diet. The TMEn content of ethanol-extracted CM was 2,302 kcal/kg as compared with 2,426 kcal/kg for untreated CM. The data indicate no advantage of oligosaccharide removal with regard to the nutritive worth of canola meal.
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PMID:Oligosaccharides in canola meal and their effect on nonstarch polysaccharide digestibility and true metabolizable energy in poultry. 816 61

In order to determine whether the changes in the activities and mRNA levels of enzymes involved in intermediary carbon metabolism previously observed in glucose-limited continuous cultures (Sierkstra et al., 1992a) were glucose specific, we have analysed their regulation in a galactose-limited continuous culture of Saccharomyces cerevisiae. The Vmax of the galactose uptake system was shown to be dilution rate (D) dependent, comparable with the high-affinity glucose uptake. The maximum uptake was observed at D 0.2 h-1 (0.25 mmol min-1 per g) and the minimum uptake (0.1 mmol min-1 per g) at D 0.05 h-1 and 0.3 h-1. The aerobic fermentation of galactose occurred at D 0.275-0.3 h-1 which is identical to the results obtained in glucose-limited continuous cultures of this strain. Because galactose is not a repressing carbon source, this demonstrates that the Crabtree effect is not mediated by, or in any way related to glucose repression. Moreover, invertase and hexokinase I mRNA levels (both subject to glucose repression at the transcriptional level) were present when the yeast produced ethanol in galactose- and glucose-limited continuous cultures. In glucose-limited continuous cultures a decrease in alcohol dehydrogenase (I and II) mRNA levels and activity and phosphoglucomutase activity was observed with increasing dilution rates. In addition, at D 0.3 h-1, when the yeast produced ethanol, glucose-6-phosphate dehydrogenase and pyruvate decarboxylase were induced and a decrease in respiration was observed.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Regulation of glycolytic enzymes and the Crabtree effect in galactose-limited continuous cultures of Saccharomyces cerevisiae. 836 13

Cells of the fission yeast Schizosaccharomyces pombe were permeabilized by treatment with toluene-ethanol. The permeabilized cells lost the bulk of the internal trehalose pool while most of the alkaline phosphatase, invertase, alpha-glucosidase, or neutral trehalase activities located inside the cells remained unaffected. This system was used as an in situ assay to determine the involvement of trehalose in enzyme protection during thermal treatments. The addition of trehalose to suspensions of permeabilized cells resulted in a sugar-dependent thermoprotection of the internal marker enzymes. This approach demonstrates that in whole cells of the fission yeast trehalose plays a physiological role as a protective molecule against thermal denaturation of cellular enzymes.
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PMID:Increased thermal stability of the enzyme content in permeabilized whole cells from the fission yeast Schizosaccharomyces pombe by exogenous trehalose and other compounds. 859 Apr 7


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