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)

1. Rat kidney lysosomal glycoproteins, prelabelled in the N-acetylneuraminic acid and polypeptide portions with N-acetyl[(3)H]mannosamine and [(14)C]lysine, or with N-acetyl-[(14)C]glucosamine, were incubated under various conditions. Autolytic cleavage of labelled N-acetylneuraminic acid and peptide was maximum at pH5.0. 2. N-Acetylneuraminic acid was released more rapidly than peptide during incubation at 37 degrees or 4 degrees C at pH5. p-Nitrophenyloxamic acid, an inhibitor of bacterial neuraminidase (Edmond et al., 1966), inhibited the cleavage of N-acetylneuraminic acid and peptide, and also inhibited cathepsin D activity. 3. Galactono-, mannono-, and glucono-lactone, inhibitors of the corresponding glycosidases, blocked the autolytic cleavage of N-acetyl[(14)C]glucosamine and protein without inhibiting beta-N-acetylhexosaminidase or cathepsin D activity. These findings suggest that the carbohydrate side chains protect the polypeptide portion of the lysosomal glycoproteins against proteolytic attack by lysosomal cathepsins. 4. In electrofocusing experiments, autolysis was minimized by adding 0.1% p-nitrophenyloxamic acid to the media used for extraction and electrofocusing, and by maintaining an alkaline pH (pH8.8-9) during extraction and dialysis. Arylsulphatase occurred in two forms with pI values of 4.4 and 6.4-6.7, and beta-glucuronidase in two forms with pI values of 4.4 and 6.1. When [(14)C]lysine and N-acetyl[(3)H]mannosamine were given to rats 1.5 and 1 h before killing, (14)C and (3)H were largely restricted to highly acidic glycoprotein species with pI values of 2.1-5.1. 5. When a lysosomal extract was adjusted to pH5 and incubated at 20 degrees C for 16h and then at 37 degrees C for 1 h before electrofocusing, 32 and 58% of the labelled peptide and N-acetylneuraminic acid was cleaved and the pI values of the labelled glycoproteins were markedly increased. About 80% of the acidic form of arylsulphatase and beta-glucuronidase was recovered with the basic form, and the pI of the basic form of both enzymes rose to 7.0. Similar, though less marked changes, were observed when a lysosomal extract was kept at pH5 for 2h at 4 degrees C before electrofocusing. 6. When an acidic lysosomal fraction (pI4.2-4.6) was incubated at pH5 for 2.5h and refocused, 80% of the arylsulphatase now occurred in two forms with pI values of 5 and 6.4. When a basic lysosomal fraction (pI5.8-6.4) was similarly incubated, the pI of arylsulphatase increased from 6.4 to 7.2. The relative increase in pI of arylsulphatases was accompanied by a proportional loss of N-acetylneuraminic acid from the glycoprotein associated with these forms. 7. These experiments show that lysosomal glycoproteins and two representative hydrolases, when exposed to a mildly acidic pH, readily undergo autolytic degradation and their pI values increase. These observations may have a bearing on the origin of the molecular heterogeneity of the lysosomal enzymes.
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PMID:Autolysis of glycoproteins in rat kidney lysosomes in vitro. Effects on the isoelectric focusing behaviour of glycoproteins, arylsulphatase and beta-glucuronidase. 445 20

The total protein content and the activities of lysosomal hydrolases (arylsulphatase, alkaline and acid phosphatases, beta-glucuronidase, beta-N-acetylhexosaminidase, alpha-L-fucosidase and beta-galactosidase) in the uteri of ovariectomized rabbits treated with different concentrations of progesterone, oestradiol-17 beta and a combination of progesterone and oestradiol were determined. The enzyme activities were also measured in the reproductive organs of rabbits induced to superovulate by PMSG and hCG. In superovulated and steroid-treated rabbits, the changes in lysosomal hydrolases were more obvious in the endometrium than the myometrium. Except for the myometrial alkaline phosphatase and beta-galactosidase and the endometrial alkaline phosphatase, there were no significant changes in the solubilities of hydrolases after treatment with steroids. beta-Galactosidase levels were significantly higher in the ovariectomized rabbits treated with progesterone. An antagonistic effect of oestradiol and progesterone was observed with respect to uterine weight, protein content and enzyme activities in the ovariectomized rabbits treated simultaneously with oestradiol and progesterone.
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PMID:Hormonal regulation of lysosomal hydrolases in the reproductive tract of the rabbit. 622 Jan 45

The beta-N-acetylhexosaminidase, beta-glucuronidase, alpha-galactosidase, beta-galactosidase and alpha-L-fucosidase activities, in six different species of molluscs, have been studied. The optimum pH was acid in all cases, in agreement with the lysosomal origin of these enzymes. They generally show several pI in their isoelectrofocusing profiles. Kinetic studies with enzymes having several activities in one protein, i.e. beta-N-acetylhexosaminidase and beta-galactosidase, have been carried out with mixed substrates in order to determine the occurrence of several active sites. The action of these enzymes on glycosidic rests containing natural substrates has been studied by enzymatic hydrolysis.
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PMID:[Glycosidases of various mollusks: general properties, kinetic studies and action on natural substrates]. 629 19

Castanospermine (1,6,7,8-tetrahydroxyoctahydroindolizine) was tested against a variety of commercially available glycosidases and found to be a potent inhibitor of almond emulsin beta-glucosidase, and also to inhibit fungal beta-xylosidase. This alkaloid was inactive on yeast alpha-glucosidase, alpha- or beta-galactosidase, alpha-mannosidase, beta-N-acetylhexosaminidase, beta-glucuronidase, alpha-L-fucosidase. Fifty-percent inhibition of beta-glucosidase required about 10 micrograms/ml of castanospermine. The amount of inhibition was uniform throughout the time course, and the inhibition with regard to substrate concentration (p-nitrophenyl-beta-D-glucopyranoside) appeared to be of the mixed type. Castanospermine was also a potent inhibitor of beta-glucocerebrosidase when assayed with fibroblast extracts using either a fluorimetric or a radioactive assay. Interestingly enough, castanospermine also inhibited the lysosomal alpha-glucosidase, and this inhibition required comparable levels of alkaloid to that required for inhibition of beta-glucocerebrosidase. However, a number of other lysosomal glycosidases were not sensitive to castanospermine (i.e., alpha- or beta-galactosidase, alpha- or beta-mannosidase, alpha- or beta-L-fucosidase, beta-N-acetylhexosaminidase, beta-glucuronidase).
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PMID:Castanospermine, a tetrahydroxylated alkaloid that inhibits beta-glucosidase and beta-glucocerebrosidase. 640 22

In porcine interareolar placental epithelia, the following enzymes were demonstrated by histochemical methods after 30, 58, 80, 100, and 110 d of pregnancy, respectively: beta-N-acetylhexosaminidase, beta-galactosidase, beta-glucuronidase, alpha-mannosidase, acid phosphatase, alkaline phosphatase, nonspecific esterases, cytochrome oxidase, 5-nucleotidase, leucine aminopeptidase, adenosine triphosphatase, diaphorases (NADH, NADPH), glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, succinate dehydrogenase, isocitrate dehydrogenase (NAD, NADP), beta-hydroxybutyrate dehydrogenase, glycero-3-phosphate dehydrogenase, NAD-glycero-3-phosphate dehydrogenase, glutamate dehydrogenase (NAD, NADP), lactate dehydrogenase. The results show that most of the enzyme activities remained almost unchanged during the period of investigation. Only G-6-PDH and 6-PGDH activities increased within the uterine epithelium and nonspecific esterase activity within uterine as well as chorionic epithelia during the 2nd half of pregnancy. Within chorionic and uterine epithelia, hydrolases but not dehydrogenases demonstrated a higher activity at the bases of chorionic villi as compared to the apices and flanks of the latter. The action and influence of the demonstrated enzymes on metabolism, energy transfer, secretory, and resorptive activities of chorionic and uterine epithelia are discussed.
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PMID:[Enzyme histochemical studies of the swine placenta. Histoptics of enzymes in interareolar placental epithelia]. 643 35

1. Hyaluronate extracted from rooster comb was digested by a mixture of beta-N-acetylhexosaminidase and beta-glucuronidase with simultaneous dialysis for 96 h. 2. The produjct, yielding 99.6% of a mixture of mono- and oligo-saccharides, was purified by gel chromatography and analysed for glucuronic acid, N-acetylglucosamine and other sugars. 3. The oligosaccharide portion was chromatographed on DEAE-cellulose, and the effluent fractions were analysed for glucuronic acid and N-acetylglucosamine, reduced with NaBH4, digested by beta-N-acetylhexosaminidase and subjected to acid hydrolysis and glucosamine determination. 4. GlcNAc-GlcA-GlcNAc, GlcA-GlcA-GlcNAc and GlcA-GlcA-GlcA-GlcNAc were the oligosaccharides obtained, which resulted from the transferase activity of the enzymes and represented 57% of the digestion products. The results demonstrate that this hyaluronate is an unbranched polymer of approximatey equal amounts of glucuronic acid and N-acetylglucosamine. The data also indicate that if this glycosaminoglycan contains any of the neutral sugars for which it was analysed, their concentration must be less than 0.020% of the sum of the known components.
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PMID:Sequential hydrolysis of hyaluronate by beta-glucuronidase and beta-N-acetylhexosaminidase. 645 78

The chromosome localization and gene synteny of soluble malate dehydrogenase (MDH1), soluble isocitrate dehydrogenase (IDH1), mitochondrial superoxide dismutase (SOD2), phosphoglucomutase-3 (PGM3), mitochondrial malate dehydrogenase (MDH2), beta-glucuronidase (GUSB), nucleoside phosphorylase (NP), pyruvate kinase M2 (PKM2), hexosaminidase A (HEXA), inosine triphosphatase (ITPA), and N-acetyl-alpha-D-galactosaminidase (NAGA) were determined in the rhesus monkey using somatic cell hybrids. Comparison with the human and Pongidae syntenic groups shows that chromosome banding homologies do not always correlate with gene mapping data.
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PMID:Complex chromosome homologies between the rhesus monkey (Macaca mulatta) and man. 682 71

Iduronate sulfatase was purified from human liver for an investigation of the degradative pathway of dermatan sulfate. An overall 80-fold purification was achieved and, more importantly, the preparation was free of alpha-L-iduronidase, beta-glucuronidase, N-acetylgalactosamine 4-sulfate sulfatase (arylsulfatase B) and highly enriched in beta-N-acetylhexosaminidase. The liver enzyme appeared to be composed of several molecular species. The enzyme activity was optimal at pH 4.0 and its Km was 10--20 microM with sulfoiduronyl sulfoanhydromannitol. Chloride was inhibitory at high concentration and among divalent metal ions, only copper was inhibitory. Nitrocatechol sulfate was not a substrate, but did show competitive inhibition. Its Ki for iduronate sulfatase was similar to its Km for arylsulfatase, suggesting a similarity in the substrate binding sites of iduronate sulfatase and arylsulfatases.
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PMID:Purification and some properties of human liver iduronate sulfatase. 695 Sep 34

To elucidate the mode of the exertion of glycosidase activities in the catabolism of the tissue glycosaminoglycans (GAG), the terminal monosaccharides of the carbohydrate chains of urinary GAG in the most prominent subfraction (40% Fr-1.25 M Fr) among the subfractions obtained in a previous paper (Endo et al. 1980a) were investigated. The results of determination of the reducing hexuronic acid and N-acetylhexosamine before and after digestion of the subfraction with beta-glucuronidase and beta-N-acetylhexosaminidase, together with previous data indicated that 0.36 and 0.37 mol of glucuronic acid and N-acetylgalactosamine, respectively, per mol of the subfraction were located at the non-reducing terminals of the carbohydrate chains. The remaining portion (0.27 mol per mol) of the non-reducing ends might be mostly occupied by the sulfated N-acetylgalactosamine residues. On the other hand, 0.25, 0.16 and 0.34 mol of glucuronic acid, N-acetylgalactosamine and xylose, respectively, per mol of the subfraction were indicated to the present at the reducing terminals of the carbohydrate chains. The remaining portion (0.25 mol per mol) of the reducing ends might be mostly occupied by the galactose residues and/or the N-acetylgalactosamine 4-sulfate residues. The present observations provided with evidence for the action of endo-beta-glucuronidase and endo-beta-N-acetylhexosaminidase on the tissue GAG, specifically on chondroitin sulfates.
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PMID:Terminal monosaccharides of carbohydrate chains of glycosaminoglycans in normal human urine. 720 66

The activity of the lysosomal enzymes acid phosphatase, beta-glucuronidase, alpha-mannosidase and hexosaminidase were determined in CSF obtained from patients with proven bacterial meningitis and from patients with various other diagnoses. The mean value for CSF beta-glucuronidase from bacterial meningitis was elevated 73-fold when compared to the aggregate mean of all control groups. Acid phosphatase and alpha-mannosidase means were 26-fold and 33-fold elevated respectively while hexosaminidase was threefold elevated. Measurement of CSF acid phosphatase and beta-glucuronidase should prove a rapid useful test in establishing the diagnosis of bacterial meningitis. Chromatography of CSF samples on DEAE Sephadex allowed the resolution of hexosaminidase and beta-glucuronidase into individual isozymes. The ratio of hexosaminidase A to hexosaminidase B was generally higher in CSF from patients with bacterial meningitis but was very variable. The isozyme distribution for beta-glucuronidase was identical to that found in serum and no differences in pattern were found between patients and control subjects.
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PMID:CSF lysosomal hydrolase activity as an aid in the diagnosis of bacterial meningitis. 721 93


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