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:3.2.1.23 (beta-galactosidase)
14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Nine healthy volunteers were studied before, during, and after ingesting a fermented dairy product containing Lactobacillus acidophilus, Bifidobacterium bifidum, and mesophilic cultures (Streptococcus lactis and S cremoris) for 3 wk. Hydrogen and methane productions and fecal beta-galactosidase and beta-glucosidase activities were measured as indicators of fermentation capacity of the colonic flora. Fecal concentrations of nitroreductase, azoreductase, and beta-glucuronidase, which may be implicated in colonic carcinogenesis, were also assessed. Hydrogen and methane productions, fecal beta-galactosidase, beta-glucuronidase, and azoreductase activities did not change over three 3-wk periods whereas fecal beta-glucosidase activity increased (42 +/- 6, 91 +/- 12, and 40 +/- 6 IU/g N, P less than 0.01) and nitroreductase decreased (0.87 +/- 0.13, 0.54 +/- 0.11, and 0.57 +/- 0.08 IU/g N, P less than 0.05).
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PMID:Effect of chronic ingestion of a fermented dairy product containing Lactobacillus acidophilus and Bifidobacterium bifidum on metabolic activities of the colonic flora in humans. 211 57

The activities of alpha- and beta-glucosidase, beta-galactosidase and beta-N acetylglucosaminidase were assessed at acidic pH by fluorimetry using the appropriate 4-methylumbelliferyl substrate in four Mycoplasma species (M. pneumoniae, M. gallisepticum, M. hominis and M. capricolum) and in Acholeplasma laidlawii. The glycosidase activities were in a low range (0.1-4.2 nmole per h per mg protein) with the exception of higher activities of beta-N-acetylglucosaminidase in A. laidlawii. The enzyme levels of a virulent and a nonvirulent strain of M. pneumoniae were comparable. Despite the very sensitive assay, neuraminidase activity was not detected in M. pneumoniae and M. gallisepticum. No induction of alpha-glucosidase could be demonstrated for M. pneumoniae or A. laidlawii. At least part of the glycosidase activities was localized in the membrane fraction of all mycoplasmas studied. This may support the hypothesis that pathogenic mycoplasmas, being membrane parasites, may modify, by their glycosidases, some host cell glycoconjugates. However, our study did not distinguish the pathogenic mycoplasmas to possess a characteristic glycosidase profile.
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PMID:Glycosidase activities of mycoplasmas. 211 90

Two enzymes that hydrolysed lactose were purified essentially to homogeneity from cell extracts of the oleaginous yeast Trichosporon cutaneum. One enzyme of Mr 120,000 had properties typical of a beta-galactosidase (EC 3.2.1.23). It hydrolysed lactose, lactulose and nitrophenyl-beta-D-galactosides. The enzyme required K+ or Rb+ for activity, and other monovalent cations tested were not effective. Enzyme activity was abolished by EDTA and stimulated by Mg2+, Mn2+ and Ca2+. The beta-galactosidase was induced by lactose, galactose, lactulose and lactobionic acid. The other enzyme, a beta-glycosidase (EC 3.2.1.21) of Mr 52,000 showed no ionic requirements and it hydrolysed lactose, nitrophenyl-beta-D-galactosides, 4-nitrophenyl-beta-D-glucoside, cellobiose, laminaribiose, laminaritriose and sophorose, but not gentiobiose, 4-nitrophenyl-beta-D-mannoside or sucrose. This enzyme was induced by lactose, galactose and lactulose, and also by cellobiose.
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PMID:Purification and properties of two lactose hydrolases from Trichosporon cutaneum. 212 10

Cyclophellitol [1S,2R,3S,4R,5R,6R)-5-hydroxymethyl-7-oxabicyclo[4,1,0] heptane-2,3,4-triol) was tested against 9 glycosidases and found to be a specific inhibitor of almond beta-glucosidase. Cyclophellitol inhibited almond beta-glucosidase activity by 50% at 0.8 micrograms/ml and was a competitive inhibitor of almond beta-glucosidase as revealed by Lineweaver-Burk plot. Cyclophellitol was inactive against yeast alpha-glucosidase, beta-galactosidase, beta-glucuronidase, alpha-L-fucosidase, end-beta-N-acetyl glucosaminidase, alpha-mannosidase, and cellulase. It was weakly active toward fungal beta-xylosidase. Cyclophellitol-treated almond beta-glucosidase was equally suppressed after dialysis; thus cyclophellitol is likely to bind to almond beta-glucosidase irreversibly. The inhibitor was found by fluorimetric assay to be active against beta-glucosidase but inactive toward alpha-glucosidase in Molt-4 microsomal fraction. It also inhibited Molt-4 beta-glucocerebrosidase completely at 2 micrograms/ml when the enzyme was assayed with a synthetic labeled substrate, and the inhibitory activity was more than one hundred times higher than that of nojirimycin, castanospermine, or of deoxynojirimycin. Mice administered 1 mg of cyclophellitol daily for 5 days began to exhibit severe abnormalities of nervous system similar to those found in Gaucher's mouse.
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PMID:Biological activities of cyclophellitol. 214 35

Previous studies have shown that bovine retinas incubated with [3H]galactose incorporated it, unmodified, into large molecules. Light and electron microscope autoradiography showed a significant proportion of the label to be in cone inner segments, and pulse-chase studies showed it was subsequently transported to the synaptic pedicles. In this report, evidence is presented to show that the galactose-labelled macromolecules are resistant to hydrolysis by proteolytic enzymes, testicular hyaluronidase, chondroitinase ABC, beta-glucosidase and beta-glucuronidase, but are readily degraded by alpha-amylase and beta-galactosidase, and to a lesser extent by beta-amylase. Treatment with alpha-amylase also leads to specific removal of radioactivity from cone inner segments and pedicles, as judged by light-microscopic autoradiography. These studies appear to indicate that the cone-specific galactose label is in glycogen or glycogen-like molecules.
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PMID:D-[3H]galactose incorporation into glycogen in retinal cone cells. 231 72

1. Tests for glycosidases were performed in homogenates of Brachionus plicatilis. 2. Hydrolytic activity was detected with the following substrates: (a) with synthetic substrates (NP = 4-nitrophenyl): NP-alpha- and NP-beta-D-glucopyranoside, NP-alpha- and NP-beta-D-galactopyranoside, NP-N-acetyl-beta-D-glucosaminide, NP-N-acetyl-beta-D-galactosaminide, NP-alpha- and NP-beta-D-mannopyranoside and NP-alpha-L-fucopyranoside; (b) with disaccharides: sucrose, maltose, trehalose, isomaltose, cellobiose, gentiobiose and lactose; (c) with polysaccharides: laminarine, carboxymethyl-cellulose, avicel, Micrococcus luteus (for lysozyme) and 4-nitrophenyl-alpha-D-maltoheptaoside (for amylase). 3. The pH dependence of the glycosidase activities was determined. 4. The distribution of enzyme activities within fractions from the homogenate was studied in order to localize them within the cell. 5. Proteins from Brachionus homogenate were separated by SDS-gel electrophoresis and the positions of the following glycosidase activities were detected by assays performed on the gels (estimated molecular weights in parentheses): alpha-glucosidase (250,000); beta-glucosidase (200,000); beta-galactosidase (70,000); N-acetyl-beta-glucosaminidase (60,000).
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PMID:Glycosidases in Brachionus plicatilis (Rotifera). 232 73

A biochemical scheme was developed by which strains of Streptococcus constellatus, Streptococcus intermedius, and Streptococcus anginosus can reliably be distinguished from within the "Streptococcus milleri group." Strains identified as S. intermedius were differentiated by the ability to produce detectable levels of alpha-glucosidase, beta-galactosidase, beta-D-fucosidase, beta-N-acetylgalactosaminidase, beta-N-acetylglucosaminidase, and sialidase with 4-methylumbelliferyl-linked fluorogenic substrates in microdilution trays after 3 h of incubation at 37 degrees C, together with the production of hyaluronidase. Strains of S. constellatus and S. anginosus were differentiated by the production of alpha-glucosidase and hyaluronidase by the former and the production of beta-glucosidase by the latter. The majority of strains of the S. milleri group obtained from dental plaque were identified as S. intermedius, as were most strains isolated from abscesses of the brain and liver. Strains of S. constellatus and S. anginosus were from a wider variety of infections, both oral and nonoral, than were strains of S. intermedius, with the majority of strains from urogenital infections being identified as S. anginosus.
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PMID:Phenotypic differentiation of Streptococcus intermedius, Streptococcus constellatus, and Streptococcus anginosus strains within the "Streptococcus milleri group". 238 Mar 75

Dextran blue decreases the activity of lysosomal acid cholesteryl esterase of rat liver at a concentration from 0.25 M to 10 M without altering acid phosphatase, acid beta-galactosidase and beta-glucosidase activities. The dextran blue filled lysosomes with a high degree of purity prepared by centrifugation over the linear sucrose density gradient contained insignificant impurities (up to 19%) of protein from other organelles. The specific activity of acid phosphatase, beta-galactosidase and beta-glucosidase was increased 35-40-fold in this fraction, whereas the activity of acid cholesteryl esterase rose but 14.7-fold. Chromatography on a Sepharose 2B column of the digitonin-digested native and dextran-containing lysosomes attests to the formation of large dextran aggregates with lysosomal matrix proteins. Since aggregation of dextran blue with acid phosphatase, beta-galactosidase and beta-glucosidase does not affect their activities, it is concluded that to bring about hydrolysis of lipoprotein cholesterol esters, it is necessary that cholesteryl esterase be associated with hydrophobic macromolecules. Moreover, dextran blue can be used for simulation cholesterol esters deposition in lysosomes.
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PMID:[Inhibition of liver lysosomal cholesterol esterase activity in rats by dextran blue in vivo and in vitro]. 240 93

Adult rats that were maintained on a low-carbohydrate intake showed rapid increase in the activities of sucrase, maltase, and lactase along the length of the small intestine when they were fed a high-starch diet. In the present study, we have identified these activity increases, and showed that they reflect proportional accumulations in enzyme-protein of sucrase-isomaltase (EC 3.2.1.10, 3.2.1.48), maltase-glucoamylase (EC 3.2.1.20), and neutral lactase (EC 3.2.1.23). It was determined that each of these enzymes exists in adult rat intestine in single immunoreactive form and accounts as a group for all sucrase, cellobiase, and most maltase and lactase activities. Dietary change from low to high carbohydrate (starch) resulted in an increase in [3H]leucine accumulation in each of the enzymes, without a change in the amount of label accumulation in total intestinal proteins. The increase in label accumulation in the brush-border carbohydrase pools was matched generally by proportional elevation in the pool concentrations of sucrase-isomaltase and lactase but not maltase. These studies suggest that the elevation of intestinal carbohydrase concentrations induced by high-carbohydrate feeding may involve selective stimulation of their synthesis.
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PMID:Nature of elevated rat intestinal carbohydrase activities after high-carbohydrate diet feeding. 241 70

One of the final steps in epidermal differentiation is the conversion of glucosylceramides to ceramides, which presumably is mediated by a beta-glucosidase activity. In the present manuscript, it is demonstrated that pig epidermis contains beta-glucosidase activity which is 3.3-times greater than alpha-glucosidase and 5-times greater than beta-galactosidase. This beta-glucosidase was found to be maximally active between pH 3.0 and essentially inactive at pH 9.0. In a standard assay, a disk of epidermis (8 mg dry weight) was submerged in 1 ml of 50 mM acetate buffer (pH 4.7) containing 150 mM NaCl and 15 mM p-nitrophenyl-beta-D-glucopyranoside at room temperature. Reaction was stopped by addition of 4 ml of 100 mM (pH 9.0) borate buffer and the supernatant was transferred to a separate tube. The nitrophenylate anion was then measured spectrophotometrically at a wavelength of 405 nm. Under these conditions, product formation was linear for at least 90 min and an apparent Km of 244 microM was estimated for the synthetic substrate. When the amount of epidermis in the assay was varied, the formation of product per unit of time remained proportional to the amount of epidermis. The level of beta-glucosidase activity was enhanced slightly by the inclusion of sodium taurocholate.
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PMID:Beta-glucosidase activity in porcine epidermis. 249 22


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