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:3.2.1.31 (beta-glucuronidase)
7,680 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Contact between human neutrophils and aggregated immunoglobulin G bound to micropore filters has been studied as a model of the pathogenesis of tissue damage in immune complex disease. Contact with this surface, as well as with plain filters and polystyrene petri dishes, induced neutrophils to elaborate superoxide anion and hydrogen peroxide and to generate chemiluminescence, which has been attributed to singlet oxygen. Pretreatment of the cells with cytochalasin B decreased these activities but increased release of lysosomal beta-glucuronidase, suggesting that degranulation and the burst of oxygen metabolism that characterizes phagocytes are independently regulated functions. Toxic oxygen metabolites released from neutrophils are highly reactive and could mediate tissue injury at sites of inflammation.
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PMID:Elaboration of toxic oxygen by-products by neutrophils in a model of immune complex disease. 18 1

The effects of DMSO are thought to result from the formation of hydrogen bonds with proton-donor groups on biopolymers, which are stronger than those formed with water. Since DMSO contains methyl groups, however, effects on hydrophobic bonding in proteins could be expected at higher DMSO levels. Our studies of the effects of DMSO on model subunit proteins can be interpreted in the above terms. At a concentration of 20% or less, DMSO changed glutamate dehydrogenase into the inactive monomer and the effects were fully reversible with the activator (ADP). Higher DMSO levels resulted in irreversible inactivation. The predominant effect noted on beta-glucuronidase was irreversible inactivation by 20% or more DMSO at 37 degrees C. Purified beta-glucuronidase exhibited an activation in 20% DMSO at high substrate levels; this resulted from an apparent substrate inhibition in the absence of DMSO. DMSO inhibited the clotting of fibrinogen by purified thrombin, but the major effect appeared to be due to competition between thrombin and DMSO for binding sites on fibrinogen. These effects appear to be largely due to interactions between DMSO and hydrophobic bonding in fibrinogen, although DMSO also appears to interfere with the aggregation of fibrin monomers through its effects on hydrophilic groups. These results suggest that reversible alterations in protein structure are the major effect of exposure of subunit proteins to low DMSO levels at low temperatues, while irreversible denaturation of subunit proteins may be an appreciable effect a higher temperatures and higher DMSO concentrations.
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PMID:Effects of dimethyl sulfoxide on subunit proteins. 23 13

A chemotactic peptide CHO.Met.Leu.Phe.OH has been synthesized classically using the mixed anhydride procedure. The formyl group was introduced by coupling formic acid in the presence of dicyclohexylcarbodiimide to the partially protected triptide. The final product was obtained by treatment of the intermediate CHO.Met.Leu.Phe.OBzl with hydrogen fluoride. The ED50 of the peptide in the Boyden chamber assay was 7 x 10(-11) M; in the lysozyme release assay 2.4 x 10(-10) M and in the beta-glucuronidase release assay 2.6 x 10(-10) M. In a radioreceptor assay the ID50 of the peptide was 3.3 x 10(-10) M.
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PMID:Synthesis of Nalpha-formyl-Met-Leu-Phe-OH: an inducer of chemotaxis in peritoneal polymorphonuclear neutrophils. 42 7

Neuronal ceroid-lipofuscinosis is characterized by pigmentary degeneration of the retina, psychomotor degeneration, epilepsy and intracellular deposition of ceroidlipofuscin. Recent reports have suggested that deficiency of peroxidase is the basic genetic defect. However, deficiency of myeloperoxidase could be demonstrated in some but not all patients; this deficiency was noted only when p-phenylenediamine (PPD) was used as hydrogen donor and could not be confirmed with guaiacol. We found that horseradish peroxidase (HR-P) oxidized PPD in the absence of added H2O2. The oxidative product of PPD showed the same absorption spectrum as the peroxidative product. The oxidation of PPD by HR-P was not inhibited by catalase or superoxide dismutase. In addition, catalase oxidized PPD in the presence of H2O2. Soluble and granular fractions obtained from human polymorphonuclear leukocytes (PMN) also oxidized PPD in the absence of H2O2. Addition of H2O2 inhibited the oxidation of PPD in some cell fractions. This inhibition could be partially eliminated by dialysis of the cell fractions. Thus, PPD is not a suitable hydrogen donor for the study of peroxidase. This may explain the variable results obtained by the previous investigators. In contrast, guaiacol did not show these undesirable characteristics. The PMN peroxidase (measured with guaiacol), catalase, beta-glucuronidase, acid and alkaline phosphatases were studied in individuals from three families with juvenile neuronal ceroid-lipofuscinosis. Family 1: an affected boy and healthy parents; all showed normal enzyme activities in both soluble and granular fractions. Family 2: two affected sisters, one healthy sib and mother, and Family 3: one affected boy; all showed reduced peroxidase activities in the granular fractions. Other enzymes were normal. The role of peroxidase deficiency in the pathogenesis of neuronal ceroid-lipofuscinosis is not clear. The basic defect of this syndrome remains uncertain.
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PMID:Neuronal ceroid-lipofuscinosis. Studies of granulocyte enzyme activities. 65 Feb 51

Urine samples containing diazolo- and triazolobenzodiazepines and metabolites were hydrolyzed with beta-glucuronidase and extracted with methylene chloride. The extracts were treated with methyl iodide, methylene chloride, and tetrahexylammonium hydrogen sulfate in basic solution to form the methyl derivatives of the drugs and metabolites. GC/MS analysis resulted in the following test characteristics: day-to-day precision at 360 ng/mL (120 ng/mL for the triazolobenzodiazepine metabolites) was 2.4 to 5.5% CV; calibration curves were linear to 6000 ng/mL (1000 ng/mL for the triazolobenzodiazepine metabolites), and operational limits of quantitation were in the range 13-25 ng/mL.
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PMID:Confirmation of low concentrations of urinary benzodiazepines, including alprazolam and triazolam, by GC/MS: an extractive alkylation procedure. 129 2

beta-Glucuronidase from bovine liver was adsorbed to the adsorbents prepared with CH-Sepharose 4B and either the competitive inhibitor or its analogs such as p-aminophenyl 1-thio-beta-D-glucuronic acid, -glucoside, -galactoside, and N-acetyl glucosaminide. The adsorbed enzyme was eluted at 0.1 or 0.5 M NaCl by a stepwise gradient. Chromatography of the enzyme was also performed by using the adsorbents prepared with Epoxy-activated Sepharose 6B and amine compounds or other compounds. In order to see whether the hydroxyl groups of the sugar parts in the ligand are necessary for the adsorption of the enzyme, chromatography was performed by using the adsorbents prepared with sugar derivatives as the ligand. As a result, it was found that beta-glucuronidase had an affinity for adsorbents prepared with either acetyl derivatives or methoxy derivatives of glycosides and CH-Sepharose 4B. From the results of elution of the enzyme with NaCl from adsorbents having amide bonding, it was clarified that the affinity of the enzyme for adsorbents without glycosides in the ligands correlated with acidity of the amide in the adsorbents. Hydrogen bond chromatography was performed with the prepared adsorbents. The enzyme was adsorbed under a high concentration of ammonium sulfate, and the elution of the adsorbed enzyme from adsorbents was examined by the degradation of salt. The enzyme was most easily eluted from aminoethyl 1-thio-beta-D-glucuronic acid-CH Sepharose 4B at 0.9 M ammonium sulfate and at 0.5 M concentration of the salt with p-aminophenyl 1-thio-beta-D-glucuronic acid-CH Sepharose 4B.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Chromatography of beta-glucuronidase from bovine liver. A study of the enzyme binding sites of prepared adsorbents. 139 4

The guinea pigs were dermally exposed to paraphenylenediamine (PPD) and in presence of an oxidising agent hydrogen peroxide for 15 and 30 d to assess their effects on some enzymes, lipid peroxidation and histamine contents in the skin. The activities of acid and alkaline phosphatases, beta-glucuronidase, gamma glutamyl transpeptidase, histidase and tyrosinase were enhanced after application of either PPD or PPD plus hydrogen peroxide. The lipid peroxidation and histamine contents also showed marked elevation following exposure to the chemicals.
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PMID:Dermal toxicity of paraphenylenediamine. 148 26

Recent studies in our laboratories have confirmed that a major unidentified metabolite of nicotine in smokers' urine was susceptible to enzymatic degradation by beta-glucuronidase to afford (S)-(-)-cotinine. In order to establish the identity of this metabolite, the quaternary ammonium conjugate, viz., (S)-(-)-cotinine N-glucuronide, was synthesized. Reaction of methyl 2,3,4-tri-O-acetyl-1-bromo-1-deoxy-alpha-D-glucopyranuronate with (S)-(-)-cotinine at 60 degrees C for 3 days affords the fully protected conjugate as the bromide salt. Deprotection was accomplished in 1 M NaOH overnight at 25 degrees C. The deprotected inner salt was isolated by Dowex-50W cation-exchange chromatography. Electrospray mass spectra of the inner salt revealed the presence of ions with m/z 353 (M + H)+, 375 (M + Na)+, and 391 (M + K)+ as well as ions resulting from loss of water and cleavage of the glycosidic bond. Proton and carbon nuclear magnetic resonance spectra established that the position of glucuronidation was the pyridyl nitrogen. The magnitude of the coupling between H1" and H2" of the sugar ring (8.71 Hz) and nuclear Overhauser enhancements were consistent with the beta-isomer of the glucuronide conjugate. The synthetic (S)-(-)-cotinine N-glucuronide was susceptible to enzymatic hydrolysis by beta-glucuronidase to afford (S)-(-)-cotinine. Application of a cation-exchange high-performance liquid chromatographic method enabled the collection of a fraction containing (S)-(-)-cotinine N-glucuronide from a smoker's urine. The electrospray mass spectrum of this fraction contained ions consistent with the presence of (S)-(-)-cotinine N-glucuronide. The concentrated fraction was subjected to enzymatic hydrolysis by beta-glucuronidase to afford (S)-(-)-cotinine.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Characterization of the glucuronide conjugate of cotinine: a previously unidentified major metabolite of nicotine in smokers' urine. 164 59

The objectives of the study were to determine whether the follicular (F; days 6-11) and luteal (L; days 16-21) phases of the menstrual cycle were associated with changes in starch malabsorption, stool bulking, stool mucinase, and beta-glucuronidase activities in 10 women (24.1 +/- 0.7 years old) eating a standardized low-fibre diet. Starch malabsorption, measured by breath hydrogen excretion after a breakfast of pureed chickpea (days 10 and 20) versus 10 g lactulose (days 11 and 21), decreased from 9.7 +/- 1.8 g/50 g starch ingested (F) to 6.6 +/- 1.8 g/50 g starch ingested (L) (P less than 0.05). Stool wet weight decreased from 84.5 +/- 10.1 g/day (F) to 52.2 +/- 5.8 g/day (L) (P less than 0.002). Stool dry weight decreased from 20.2 +/- 1.9 g/day (F) to 14.2 +/- 1.1 g/day (L) (P less than 0.006). Stool nitrogen excretion decreased from 1.81 +/- 0.19 g/day (F) to 0.82 +/- 0.06 g/day (L) (P less than 0.006). Stool mucinase and beta-glucuronidase activities were unaffected by the menstrual cycle. These results indicate that women eating low-fibre Western diets may be more prone to constipation during the luteal phase of the menstrual cycle.
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PMID:Starch malabsorption and stool excretion are influenced by the menstrual cycle in women consuming low-fibre Western diets. 166 73

Enterohaemorrhagic Escherichia coli O157:H7 is of major concern to the food industry due to high pathogenicity of this foodborne organism. For the detection of these bacteria a special agar medium with a fluorogenic substrate has been developed. The medium uses the characteristics of this E. coli serotype not to ferment sorbitol and not to produce beta-glucuronidase. In contrast, approximately 96% of all other strains of E. coli are sorbitol-positive and nearly all of them are beta-glucuronidase-positive. For discrimination between Proteus and E. coli O157:H7 which are both sorbitol- and beta-glucuronidase-negative, sodium thiosulphate and ferrio ammonium citrate were added. This leads to a brownish colour of the Proteus colonies due to their production of hydrogen sulphide. Growth of the gram-positive flora was inhibited by the addition of sodium deoxycholate.
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PMID:Pathogenic Escherichia coli O157:H7 and their detection. 181 28


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