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)

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

Sera from 9 persons with either biopsy-proven alcoholic liver disease or a history of chronic, excessive ethanol consumption were analyzed for their content of various hydrolases. Compared to controls, significant elevations in the following enzyme activities were seen in sera from the patient population: acid phosphatase (2.0-fold), beta-glucuronidase (2.1-fold), hexosaminidase (1.4-fold), and alpha-L-fucosidase (2.3-fold). In addition, alpha-mannosidase activity, previously reported to be unchanged in cases of hepatic cirrhosis [Reglero et al., Clinica chim. Acta 130: 155-158], (1980) was found to be significantly increased (p less than 0.001) when assays were performed at acid (pH 4.5) or intermediate (pH 5.5) hydrogen ion concentrations. Fractionation of sera on DEAE-Sephadex columns showed that the increase in alpha-mannosidase activity in the serum of patients with alcoholic liver disease was due to increases in the level of at least one 'acid alpha-mannosidase' and two intermediate pH optimum alpha-mannosidases. The general increase in the activity of a group of glycosidases is consistent with a hypothesis involving decreased clearance of glycoproteins from the blood of persons with hepatic cirrhosis.
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PMID:Serum alpha-mannosidase in patients with alcoholic liver disease. 671 94

We have isolated from monkey (Macaca radiata) brain lysosomal fraction by phosphomannan-Sepharose chromatography a protein that binds four different lysosomal enzymes, beta-hexosaminidase, beta-glucuronidase, alpha-L-fucosidase and arylsulfatase. The isolated protein which appeared in an aggregated homogeneous form on gel electrophoresis under non-denaturing conditions at both pH 8.3 and pH 5.0 was found to be heterogeneous on SDS-gel electrophoresis with molecular weights less than 67,000. Binding was partly abolished by periodate treatment or by alkaline phosphatase treatment of the lysosomal enzymes. Binding was completely abolished by pronase digestion of the binding protein. Of the different sugars tested for inhibition of binding, mannose-6-phosphate was most effective followed by mannose and N-acetyl glucosamine while glucose and fucose were ineffective.
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PMID:A binding protein for lysosomal enzymes isolated from brain by phosphomannan-sepharose chromatography. 684 56

The activities of 21 enzymes (belonging to four classes of enzymes) involved in different metabolic pathways were assayed in blood sera of healthy young and adult/elderly groups of humans, rats and pigs, to determine whether activity changes coinciding with changes in age and aging could be detected. In all three species analysed, measurable activities (performed by highly specific and sensitive techniques, generally spectrofluorimetric procedures) were found, usually following a decreasing order of: among glycosidases, beta-N-acetylglucosaminidase (NAG) > alpha-L-fucosidase > alpha-mannosidase > beta-glucuronidase > beta-galactosidase > alpha-galactosidase. In addition, among esterases very high values were found for arylesterase and acid phosphatase. By contrast, no measurable activity was found for the remaining enzymes assayed (8 hydrolases, 1 oxidoreductase, 3 transferases and 1 lyase). In the elderly group of humans, significantly higher activities (P < or = 0.05) were found for NAG, alpha-mannosidase and beta-glucuronidase in comparison to the adult and young groups. However, several activities in rats and all activities in pigs decreased with age. In conclusion, differences in the activities of 6 lysosomal glycosidases and 2 esterases (but no significant differences for another 13 enzymes belonging to several enzyme classes) are found in the sera of healthy humans, rats and pigs. These differences coincide with changes observed in aging.
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PMID:Evaluation of the activities of eight lysosomal hydrolases in sera of humans, rats and pigs of different ages. 948 85

Fasciola hepatica secretes proteolytic enzymes and other molecules that are essential for host penetration and migration. This mixture may include enzymes required for the degradation of supramucosal gels, which defend epithelial surfaces against pathogen entry. These contain hydrated mucins that are heavily glycosylated. Excretory-secretory products (ES) from F. hepatica were examined for a range of glycosidase activities, using synthetic 4-methylumbelliferyl glycosides as substrates. The ES product contained at least 8 different glycosidase activities, the most abundant of which were beta-N-acetylhexosaminidase, beta-galactosidase and beta-glucosidase. Alpha-fucosidase, beta-glucuronidase, alpha-galactosidase, alpha-mannosidase and neuraminidase were also present. Beta-N-acetylhexosaminidase and beta-galactosidase were present in multiple isoforms (at least 4), whereas beta-glucosidase appeared to exist as one isoenzyme with a pI < 3.8. All three enzymes had acidic pH optima (4.5-5.0). Ovine small intestinal mucin was degraded by ES at pH 4.5 or 7.0, with or without active cathepsin L, the major protease found in F. hepatica ES. The ability of F. hepatica ES to degrade mucin in the presence or absence of active cathepsin L suggests that cathepsin L is not essential for mucin degradation. The abundance of beta-galactosidase and beta-hexosaminidase in ES supports a role for these enzymes in mucin degradation.
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PMID:Glycosidase activity in the excretory-secretory products of the liver fluke, Fasciola hepatica. 1552 35


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