Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.31 (beta-glucuronidase)
 7,680 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. The metabolic pathways of p-nitroanisole, 4-nitro-m-cresol and methyl parathion in Malaysian prawns (Macrobrachium rosenbergii), ridgeback prawns (Sicyonia ingentis) and crayfish (Procambarus clarkii) were compared. 2. The Malaysian prawns and ridgeback prawns were shown to O-demethylate 29% and 11%, respectively, of an accumulated level of p-nitroanisole, while crayfish were able to O-demethylate 98% of the accumulated level of nitroanisole. 4-Nitro-m-cresol oxidation was not detected in either prawn species. In contrast, 5-hydroxy-2-nitrobenzaldehyde was the major metabolite formed from nitrocresol metabolism by crayfish. 3. Both prawn species readily dearylated methyl parathion to form p-nitrophenol and p-nitrophenyl conjugates. Crayfish displayed a similar trend in methyl parathion metabolism. 4. Nitroreduction was observed in the metabolism of 4-nitro-m-cresol by ridgeback prawns, which excreted 4-nitroso-m-cresol as a minor product. Reduction products were not observed in the metabolism of the three substrates by Malaysian prawns or crayfish. 5. Conjugation was overall the dominant detoxication pathway observed in the decapods. Malaysian prawns conjugated p-nitrophenol and 4-nitro-m-cresol to form the corresponding beta-D-glucosides and sulphate monoesters. Ridgeback prawns formed beta-D-glucosides in small quantities, preferring conjugation of p-nitrophenol and 4-nitro-m-cresol to form sulphates and unknown conjugates through a unique conjugation pathway. Crayfish conjugated the phenolic substrates to form exclusively the beta-glucosides. 6. The unknown conjugates formed by ridgeback prawns had chromatographic properties similar to the corresponding beta-D-glucosides but were refractory to the deconjugation by alpha- or beta-glucosidase, beta-galactosidase, aryl sulphatase and beta-glucuronidase. Phenolic conjugation ability appeared to follow the order of ridgeback prawns greater than Malaysian prawns greater than crayfish.
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PMID:Comparative metabolism of nitroaromatic compounds in freshwater, brackish water and marine decapod crustaceans. 343 90

Nineteen hydrolytic enzymes were detected in individual adult Pergamasus longicornis (Berlese) mites--amylase, hide protease, alkali phosphatase, esterase (C4), esterase lipase (C8), lipase (C14), leucine arylamidase, valine arylamidase, cystine arylamidase, acid phosphatase, phosphoamidase, alpha-galactosidase, beta-galactosidase, beta-glucuronidase, alpha-glucosidase, beta-glucosidase, N-acetyl-beta-glucosaminidase, alpha-mannosidase, and alpha-fucosidase. All but the phosphatases were detected for the first time. Tryptic and chymotryptic activity were consistently not demonstrable. Comparisons are made with saprophagous mites. No clear enzymic specialization for predation was found.
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PMID:Digestion in the soil predatory mite Pergamasus longicornis (Berlese) (Acari: Mesostigmata: Parasitidae)--detectable hydrolases. 356 25

A comparison was made in six species of animal (rat, mouse, hamster, guinea-pig, marmoset and man) of five enzyme activities associated with the hindgut microflora. Marked differences were found in the caecal activities of azoreductase, beta-glucosidase, beta-glucuronidase, nitrate reductase and nitroreductase in the four rodents, with no one species exhibiting consistently higher or lower enzyme activity. None of the laboratory animals, including the marmoset, provided an approximation of the enzyme profile associated with human faecal flora. The results indicate that it may be invalid to extrapolate the results of bacterial metabolic studies between closely related species, or from animals to man.
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PMID:Enzyme activities of the hindgut microflora of laboratory animals and man. 375 Nov 8

In human freshly prepared platelets the following lysosomal enzymes were studied: alpha-mannosidase, alpha-fucosidase, beta-galactosidase, beta-glucosidase, beta-glucuronidase, beta-N-acetylglucosaminidase and acid phosphatase. For each of the examined enzymes the conditions providing maximal activity (pH, buffer), kinetic parameters (saturating substrate concentration and Km) as well as heat stability were established. On the basis of these parameters it is suggested that many of the serum glycohydrolases may be platelet derived.
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PMID:Lysosomal enzymes in human platelets. 383 17

Male Sprague-Dawley rats were fed a purified fibre-free diet containing 5% (w/w) sodium saccharin for 4 weeks or 20 weeks and changes in caecal bacterial numbers and enzyme activities (endogenous ammonia production, beta-glucosidase, beta-glucuronidase, nitrate reductase, nitroreductase, aryl sulphatase) determined in vitro. Saccharin treatment gave marked caecal enlargement but had no effect on bacterial concentration at either treatment period, and significantly decreased beta-glucuronidase, nitrate reductase and sulphatase activities/g caecal contents. The incubation of a suspension of caecal contents from control rats with saccharin (75 mM) in vitro inhibited beta-glucuronidase and nitrate reductase activities, and ammonia production from endogenous substrates. Such changes may decrease the rate of formation of toxic bacterial products in the hindgut.
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PMID:Modification of rat caecal microbial biotransformation activities by dietary saccharin. 384 Feb 94

The commercial source of fetal bovine serum used to supplement the growth medium of human skin fibroblasts alters the activity of the lysosomal enzyme dipeptidyl aminopeptidase-1 (DAP-1). Cells grown with one serum were found to have a threefold higher level of DAP-1 than those grown with serum from another source (P less than 0.001). The effect on DAP-1 activity was specific inasmuch as no differences were found in the activities of a variety of other lysosomal and nonlysosomal hydrolases: DAP-II, DAP-III, DAP-IV, beta-glucosidase, beta-glucuronidase, and N-acetyl-beta-galactosaminidase. The effect is reversible and is observed over a wide range of cell population doublings. Cell growth kinetics were not significantly different with the different sera.
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PMID:Reversible change in the fibroblast lysosomal enzyme dipeptidyl aminopeptidase-1 (cathepsin C) related to the commercial source of fetal bovine serum in the culture medium. 389 18

Lysosomal membrane fractions were prepared from lysosomes of mouse liver by freeze-thawing in a hypotonic buffer: 54% of beta-glucosidase [EC 3.2.1.45] in lysosomes was associated with the membrane fractions, whereas 96% of beta-glucuronidase [EC 3.2.1.31] was recovered in the soluble fractions of lysosomes. beta-glucosidase was solubilized by pH 9.5 treatment or by Triton treatment of membranes. The enzyme solubilized with alkali and concentrated with (NH4)2SO4 was rapidly inactivated in a solution of pH 9.5, but could be protected against inactivation by acidic detergent. Gel filtration analysis indicated that beta-glucosidase was in an aggregated form at neutral pH and could be disaggregated by alkali and detergents. The enzyme dissociated with detergents also showed a higher activity than the alkali-treated enzyme. These results suggested that beta-glucosidase is a peripheral enzyme bound to acidic lipids in membranes. beta-Glucosidase was purified to apparent homogeneity by (NH4)2SO4 fractionation and chromatographies with Sephacryl S-300, hydroxylapatite and cation exchangers in the presence of detergents. The catalytic activity of the purified enzyme was maximally stimulated by phosphatidylserine and heat-stable protein in the presence of a low concentration of Triton X-100. The stimulation was mainly due to an increase in Vmax.
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PMID:Characterization of beta-glucosidase as a peripheral enzyme of lysosomal membranes from mouse liver and purification. 393 51

The activities of four enzymes (beta-glucuronidase, nitrate reductase and nitroreductase) in selected intestinal bacteria (Escherichia coli, Clostridium sp., Streptococcus sp., Bacteroides sp. and Lactobacillus salivarius) were measured after growth in vitro and in vivo. The five strains differed in their activities with Clostridium sp. being the most active for beta-glucosidase, beta-glucuronidase and nitroreductase, and E. coli the most active producer of nitrate reductase. Enzyme activity in vivo tended to be higher than in vitro but there were instances where the comparative activities were reversed.
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PMID:The influence of the host on expression of intestinal microbial enzyme activities involved in metabolism of foreign compounds. 393 53

The activities of six glycosidases in a rat colorectal adenocarcinoma were measured and compared with those of normal colonic mucosa. The specific activities of beta-galactosidase (EC 3.2.1.23) and beta-glucuronidase (EC 3.2.1.31) in the adenocarcinoma were similar to those of the corresponding ones in the normal mucosa, whereas those of beta-N-acetylglucosaminidase (EC 3.2.1.30), alpha-L-fucosidase (EC 3.2.1.51), alpha-galactosidase (EC 3.2.1.22) and beta-glucosidase (EC 3.2.1.21) were reduced in the former as compared with those in the latter. In the case of alpha-L-fucosidase, two forms were newly detected in the tumor. The relative abundance of three forms of beta-N-acetylglucosaminidase was quite different between the adenocarcinoma and the normal mucosa, and the level of the intermediate form in the tumor was markedly reduced. However, thermostability and Km values of two forms A and B in the tumor were not different from those of the corresponding ones in the normal tissue.
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PMID:Alteration in glycosidases from well-differentiated colorectal adenocarcinoma of rat. 404 71

Rats, mice, and hamsters were fed iota-carrageenan incorporated in a fiber-free, purified diet for 30 days, and the activities of a number of cecal microbial enzymes were determined in vitro. Carrageenan treatment produced cecal enlargement in all species, yet significantly decreased the concentration of bacteria per gram of cecal content. Azoreductase, beta-glucosidase, beta-glucuronidase, nitrate reductase, and nitroreductase activities per gram of cecal content were significantly decreased in the rat, although less consistent effects were found in these enzymes in the mouse and hamster. beta-Glucuronidase and nitrate reductase functions were increased per gram of cecal contents in the hamster. The total activity per cecum of certain of these enzymes was modified by the concomitant cecal enlargement, yet total nitroreductase activity was significantly decreased in all three rodent species. iota-Carrageenan significantly decreased the concentration of enterobacteria, staphylococci, streptococci, lactobacilli, facultative anaerobes, and the total microscopic count in the rat cecum, but did not exert any effect on bacterial viability in vitro. Although having no effect on biliary IgA antibody concentration, iota- and kappa- carrageenan when present at 50 g/kg diet increased the agglutination response of the IgA specific for the hindgut microflora.
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PMID:Influence of dietary carrageenans on microbial biotransformation activities in the cecum of rodents and on gastrointestinal immune status in the rat. 404 88


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