Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.21 (beta-glucosidase)
 3,280 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Lymphocytes, monocytes, neutrophilic granulocytes and platelets were each separated to greater than 95% purity from six normal subjects, three patients with Gaucher's disease, two heterozygotes for Gaucher's disease, and one patient with Fabry's disease. Activities of the following acid hydrolases were determined: "acid" (pH 4.0) beta-glucosidase, pH 5.0 beta-glucosidase, alpha-galactosidase, alpha-arabinosidase, alpha-mannosidase, alpha-glucosidase, beta-glucuronidase, beta-galactosidase, beta-hexosaminidase, and acid phosphatase. Enzymatic activity varied greatly with cell type and the enzyme being measured; the importance of assaying pure preparations especially for heterozygote detection is emphasized. Gaucher's disease patients' cells were found to be deficient in the pH 4.0 acid beta-glucosidase, variable in the pH 5.0 beta-glucosidase, and normal in all other acid hydrolases tested, including acid phosphatase, the activity of which is known to be elevated in plasma. Blood cells of a patient with Fabry's disease were deficient in alpha-galactosidase and normal in all other acid hydrolases tested.
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PMID:Acid hydrolases in leukocytes and platelets of normal subjects and in patients with Gaucher's and Fabry's disease. 0 20

Variable amounts of residual 4-methylumbelliferyl-beta-glucosidase activity gave rise to difficulties in the diagnosis of Gaucher's disease using spleen and particularly liver. Soluble and particulate components of beta-glucosidase, which interfere with the diagnosis, may be eliminated by preincubation of homogenates at pH 3.0 or with 100 mM sodium chloride at pH 4.0. After either of these treatments the optimum of acid beta-glucosidase was pH 4.5 and diagnosis of Gaucher's disease could be more easily made using homogenates of spleen and liver. There was residual acid beta-glucosidase activity in one of the Gaucher livers.
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PMID:Acid beta-glucosidase and the diagnosis of Gaucher's disease in liver and spleen. 2 86

Washing skin fibroblasts or leucocytes in 0.25 mol/l sucrose increases the activity of beta-glucosidase at acid pH. This effect is primarily due to removal of low levels of sodium chloride, which inhibit acid beta-glucosidase. A secondary factor for skin fibroblasts in the removal of residual phosphate buffer pH 7.3 used to wash the cells following trypsinization. As the beta-glucosidase activity of water-lysed leucocytes is higher at acid pH than that of a saline suspension of leucocytes, the former are better for the diagnosis of Gaucher's disease. However, more reliable results still may be obtained by assay of this enzyme in cultured skin fibroblasts.
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PMID:Diagnosis of Gaucher's disease in cultured skin fibroblasts and leucocytes. 11 79

Cyclophellitol, a cyclitol with an epoxide, is a novel microbial secondary metabolite that inhibits beta-glucosidase and beta-glucocerebrosidase. Daily administration of cyclophellitol induces a severe abnormality of the nervous system in mice while it has no toxicity in various cultured cells. It was shown to inhibit glucocerebrosidase in vivo significantly in mice and the content of glucocerebroside in liver, spleen, and brain was increased markedly. The enzyme activity was completely suppressed in brain, liver, spleen, kidney, and muscle. On the other hand hexosaminidase activity was not affected in all tissues. After a single administration of cyclophellitol the maximal inhibition of glucocerebrosidase was observed within 30 min in brain and liver, and the inhibition lasted for 2-4 days. A single administration of cyclophellitol also induced a severe abnormality of the nervous system known as Gaucher's-like disease in mice. Conduritol B epoxide is also known to inhibit glucocerebrosidase and induce Gaucher's like-disease in mice by repetitive injection. Cyclophellitol was shown to be more potent than conduritol B epoxide in inhibition of glucocerebrosidase and in induction of the neural abnormality.
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PMID:Inhibition of glucocerebrosidase and induction of neural abnormality by cyclophellitol in mice. 138 24

The intercellular lipids of the stratum corneum, which are highly enriched in ceramides, are critical for the mammalian epidermal permeability barrier. During the terminal stages of epidermal differentiation, the glucosylceramide content is dramatically reduced, while the content of free ceramides increases. To investigate whether beta-glucocerebrosidase (beta-GlcCer'ase) could be responsible for this change in lipid content, we characterized its activity in murine epidermis, compared enzyme activity to other murine tissues, and localized beta-GlcCer'ase activity within the epidermis. Epidermal extracts demonstrated linear 4-methylumbelliferyl-beta-D-glucose hydrolysis (to 3 h) with protein concentrations between 1 and 250 micrograms/ml. Whole epidermis contained comparable beta-glucosidase activity (9.1 +/- 0.4 nmol/min per mg DNA) to murine brain and liver, and 5-fold higher activity than spleen. Epidermal beta-glucosidase activity was stimulated greater than 15-fold by sodium taurocholate at pH 5.6, and inhibited at acidic pH (3.5-4.0). Bromoconduritol B epoxide (greater than or equal to 1.0 microM), inhibited epidermal enzyme activity by greater than 75%, while activity in brain, liver, and spleen was only inhibited by 6, 17, and 14%, respectively. Moreover, beta-GlcCer'ase mRNA expression in murine epidermis exceeded levels in liver, brain, and spleen. Finally, beta-GlcCer'ase activity was highest in the outer, more differentiated epidermal cell layers including the stratum corneum. In summary, mammalian epidermis contains an usually high percentage (approximately 75%) of beta-glucocerebrosidase activity, and the concentration of activity in the more differentiated cell layers may account for the replacement of glucosylceramide by ceramides in the outer epidermis.
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PMID:beta-Glucocerebrosidase activity in murine epidermis: characterization and localization in relation to differentiation. 143 99

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

A cDNA encoding human acid beta-glucosidase (N-acylsphingosyl-1-O-beta-D-glucoside: glucohydrolase, EC 3.2.1.45) expressed catalytically active enzyme in transfected COS-1 or infected Spodoptera frugiperda (Sf9) cells. The expression plasmid p91023(B) (p91023B/Glc) and a Baculovirus (AcMNPV/Glc) containing the cDNA were constructed and used with the respective cells. By immunoblotting a glycosylated, 63-kilodalton human acid-beta-glucosidase was detected in the transfected or infected cells. A 56-kilodalton human polypeptide was obtained after complete deglycosylation with N-Glycanase. The expressed human enzymes also had partial endoglycosidase H sensitivity. The human enzyme expressed at high levels in Sf9 cells and had normal immunologic properties. With the partially purified enzyme from Sf9 cells, intact function of active site was indicated by normal kcat and Kmapp or Kiapp values for alternative substrates or potent inhibitors, respectively. The expressed enzyme was also activated normally by the negatively charged lipid, taurocholate. The results of these studies indicate that the Baculovirus expression system could provide a convenient source of normal human enzyme for structure/function investigations. In addition, this expression system should prove useful for the identification and evaluation of putative etiologic point mutations in Gaucher disease variants with kinetically altered residual enzymes.
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PMID:Expression of functional human acid beta-glucosidase in COS-1 and Spodoptera frugiperda cells. 249 77

The genetic defect in Gaucher disease consists in a deficiency of a membrane-bound lysosomal acid beta-glucosidase. Using the radiation inactivation method, we have previously reported a subunit coupling of the mutated acid beta-glucosidase from Gaucher type 1 spleen in contrast to the normal one (Maret, A., Potier, M., Salvayre, R. and Douste-Blazy, L. (1983) FEBS Lett. 160, 93-97). We have used the same method to determine the effect of detergents on subunit coupling or uncoupling of acid beta-glucosidase in normal and Gaucher spleens. The hypothesis that detergent activation of beta-glucosidase could be due to subunit association or dissociation has been tested. The radiation inactivation size of beta-glucosidase in absence of detergent was 71,000 and 135,500 for normal and Gaucher spleen, respectively, whereas the corresponding values in presence of detergent were 84,000 and 169,000. The higher values obtained in the presence of detergent are incompatible with association or dissociation of subunits but correspond to the increase generally observed for proteins irradiated in the presence of Triton X-100.
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PMID:In vitro detergent activation of lysosomal acid beta-glucosidase in the spleen of normal and type 1 Gaucher patients is not accompanied by change in aggregation state. 250 83

The activities of beta-glucosidase as well as of alpha- and beta-galactosidase increase in the renal cortex of the rat during the early postnatal development. However, while the two galactosidases reach adult values around the end of the second week of life, beta-glucosidase activity exhibits a second steep increase after the third post-uterine week. This rise in activity correlates with the functional maturation of kidney and is confined nearly exclusively to the cytosolic isozyme. The effects of taurocholate, Triton X-100, and dexamethasone on beta-glucosidase isozymes were studied. The results suggest that taurocholate should be included in the assay medium for the measurement of the beta-glucocerebrosidase activity in the diagnosis of Gaucher's disease. For the determination of the total beta-glucosidase activity in samples containing mainly the lysosomal isozyme (perinatal kidney, isolated lysosomes) the use of Triton X-100 is recommended.
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PMID:Developmental changes of glycosidase activities in rat renal cortex. 301 25

Cellulose-acetate gel electrophoresis, a technique commonly used for the separation of human acid hydrolases, was applied to study heterogeneity in acid beta-glucosidase (EC 3.2.1.45). With this technique, three forms of beta-glucosidase were distinguishable in extracts of several tissues. The most anodic beta-glucosidase activity (band 3) represents the broad-specificity beta-glucosidase that is not deficient in Gaucher disease and is not inhibited by conduritol B-epoxide (CBE). The beta-glucosidase activity was deficient in Gaucher disease. A third beta-glucosidase activity with an intermediate mobility (band 2) was also inhibited by CBE and deficient in Gaucher disease. Band 1 and band 2 beta-glucosidase thus represent different forms of glucocerebrosidase. By adding phosphatidylserine and sphingolipid activator protein (SAP-2), monomeric glucocerebrosidase could be completely converted into a form that comigrated with band 2 beta-glucosidase of tissue extracts. The addition of phosphatidylserine only also resulted in a changed mobility of the monomeric enzyme, but the migration in this case differed from that of band 2 beta-glucosidase of tissue extracts. The electrophoretic profile of beta-glucosidase activity of tissue extracts changed upon ethanol/chloroform extraction: the two glucocerebrosidase forms were converted into a band with a mobility identical to that of band 1 beta-glucosidase. Our findings indicate that the interaction of glucocerebrosidase with phospholipid and SAP-2 has major effects on the mobility of the enzyme in the cellulose-acetate gel electrophoresis system. The findings with the cellulose-acetate gel electrophoretic system are discussed in relation to the heterogeneity in glucocerebrosidase observed with sucrose density gradient analysis, immunochemical methods and isoelectric focussing studies.
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PMID:Heterogeneity in human acid beta-glucosidase revealed by cellulose-acetate electrophoresis. 313 Jan 6


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