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)

Mouse peritoneal macrophages that had been treated with a monovalent carboxylic ionophore, monensin, selectively secreted lysosomal and nonlysosomal granular enzymes into the medium. When macrophages were incubated with 1 to 10 microM monensin, the release of beta-glucuronidase, beta-hexosaminidase and beta-galactosidase was stimulated time and does dependently. Neither the beta-glucosidase nor acid phosphatase, enzymes bound to the lysosomal membranes, however, were released by monensin. Neutral alpha-glucosidase, shown recently to be localized in nonlysosomal granules of macrophages (15), was released by monensin at concentrations lower than those required for lysosomal enzyme release. Increased release of lysosomal enzymes also took place in a manner similar to that seen with monensin-treated macrophages after treatment of macrophages with weak bases, chloroquine and ammonium chloride. Neutral alpha-glucosidase, however, was not released when chloroquine was present in concentrations that stimulated the release of lysosomal enzymes. The UDP-galactosyltransferase activity of the Golgi apparatus in the macrophages markedly decreased after treatment with low concentration of monensin.
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PMID:Stimulation of the release of lysosomal and nonlysosomal granular enzymes from macrophages treated with monensin. 643 21

Acid hydrolases from mammalian sources contain phosphorylated oligosaccharides which function as recognition markers for their receptor-mediated endocytosis by human fibroblasts. The discovery that glycopeptides derived from the slime mold, Dictyostelium discoideum, contain mannose 6-phosphate led to the suggestion that acid hydrolases from this source might also bear the marker. To test this hypothesis, the binding and endocytosis of purified beta-D-glucosidase (EC 3.2.1.21), beta-N-acetyl-D-hexosaminidase (EC 3.2.1.52), and alpha-D-mannosidase (EC 3.2.1.24) by human fibroblasts were investigated. These enzymes underwent endocytosis with efficiencies of 8.6 to 60%/mg/h, and 1 mM mannose 6-phosphate markedly inhibited their uptake (80 to 100%). The specificity of inhibition by sugar phosphates, the saturation kinetics of endocytosis, and the binding properties of D. discoideum acid hydrolases were similar to those reported for enzyme preparations derived from mammalian sources. In addition, 95 to 100% of the beta-D-glucosidase or alpha-D-mannosidase molecules from D. discoideum preparations were competent for in vitro clearance. Furthermore, the three purified acid hydrolases contain 5 to 7 mol of mannose 6-phosphate/mol of enzyme. This indicates that, unlike many mammalian enzyme preparations, most if not all of these enzyme molecules from D. discoideum contain the phosphomannosyl recognition marker.
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PMID:Acid hydrolases from Dictyostelium discoideum contain phosphomannosyl recognition markers. 644 6

The time-course of the ultrastructural changes and activities of 6 marker enzymes of subcellular particles (succinate dehydrogenase, beta-glucosidase, beta-N-acetylglucosaminidase, acid RNAse, glucose-6-phosphatase and 5'-nucleotidase) has been studied in the liver, spleen and thymus in rats administered T-2 toxin (mycotoxin produced by some Fusarium species). A pronounced difference in the effect of T-2 toxin on the organs has been found. In the liver, the toxin induced a destruction of rough endoplasmic reticulum membranes, reduced ribosome number and progressively decreased activities of most enzymes. In the spleen, early and significant ultrastructural disturbances of all the cell membrane components and simultaneous lysosomal activation were observed. The changes in the thymus were characterized by a fast development of cell hydratation, organelle swelling and necrosis of some thymocytes with parallel increase in repair processes, infiltration by phagocytes and a selective activation of lysosomal hydrolases in the end of experimental time (72 h.). The results obtained emphasize an importance of cellular and subcellular membrane alterations in the mechanism of T-2 toxin action.
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PMID:[Effect of T-2 toxin on organ ultrastructure and organelle-specific enzyme activity in rats]. 665 69

Liver fibrosis was produced in rats by subcutaneous injections of carbon tetrachloride. The effect of anti-inflammatory steroids (hydrocortisone, prednisone, dexamethasone) on the activity of serum lysosomal hydrolases (beta-N-acetylglucosaminidase, beta-glucosidase and alpha-mannosidase) was investigated in healthy and CCl4 poisoned rats. The marked increase of enzymatic activity in blood serum was observed in animals with CCl4-induced liver fibrosis. Quite opposite results were found in normal rats treated with glucocorticosteroids. In rats which were given both carbon tetrachloride and corticosteroids the obtained values of serum enzymatic activity did not have a uniform character as compared to controls or CCl4 intoxicated rats. Presumable mechanisms of the results obtained are discussed.
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PMID:Effect of anti-inflammatory steroids on the activity of selected lysosomal hydrolases in serum of rats with experimental liver fibrosis. 668 81

The activities of various glycosidases in homogenates of the small intestinal mucosa of two adult and 18 suckling tammar wallabies (M. eugenii) aged from 6 to 50 weeks were investigated. Lactase (beta-D-galactosidase), beta-N-acetylglucosaminidase, alpha-L-fucosidase and neuraminidase activities were high during the first 34 weeks post partum and then declined to very low levels. Maltase, isomaltase, sucrase and trehalase activities were very low or absent during the first 34 weeks, and then increased. The lactase activity was unusual in being greater in the distal than the middle or proximal thirds of the intestine, and in its low pH optimum (pH 4.6), inhibition by p-chloromercuribenzene sulfonate but not by Tris, and lack of cellobiase activity. These properties are those of a lysosomal acid beta-galactosidase rather than of a brush border neutral lactase. The maltase activity had the characteristics of a lysosomal acid alpha-glucosidase early in lactation and of a brush border neutral maltase in adult animals. The significance of these findings is discussed in relation to changes in dietary carbohydrates during weaning and to the mode of digestion of milk carbohydrates by the pouch young.
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PMID:Intestinal lactase (beta-galactosidase) and other glycosidase activities in suckling and adult tammar wallabies (Macropus eugenii). 678 21

This report describes a reliable and reproducible method for the identification of carriers of Type I Gaucher disease using blood platelets as the source of beta-glucosidase and 4-methylumbelliferyl-beta-D-glucoside as substrate. Platelet lysates have at least two identifiable beta-glucosidase activities with the synthetic substrate. One is maximally active at pH 5.0 in the absence of sodium taurocholate and the other at pH 5.6 in the presence of taurocholate. In platelets of Gaucher homozygotes and heterozygotes, the beta-glucosidase activity at pH 5.6 with the bile salt is reduced whereas the activity at pH 5.0 is the same in non-carriers, carriers and affected patients. In addition to differences in specific activity, the ratio of beta-hexosaminidase to beta-glucosidase activities is a useful parameter in the evaluation of the carrier state. Since carriers have normal activity of hexosaminidase and a reduced activity of beta-glucosidase, their mean activity ratio is about 70% higher than in non-carriers. Therefore we propose that the specific activity of beta-glucosidase at pH 5.6 in the presence of sodium taurocholate with the ratio of beta-hexosaminidase to beta-glucosidase serve as useful and reliable indices in the evaluation of the carrier state for Gaucher disease.
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PMID:Heterozygote detection of type I Gaucher disease using blood platelets. 679 62

The specific activities of several glycosidases (beta-N-acetylglucosaminidase, beta-D-glucosidase, alpha-D-glucosidase, beta-D-fucosidase, alpha-L-fucosidase and beta-D-galactosidase) were determined in human sera from a control group to 10 normal subjects and in four groups, each of 10 patients, with acute viral hepatitis, acute pancreatitis, acute myocardial infarction and breast cancer. The results show significantly higher activities in acute viral hepatitis for beta-N-acetylglucosaminidase, beta-D-glucosidase and alpha-D-glucosidase (p less than 0.001); in acute pancreatitis for the first two of these enzymes (p less than 0.001); and in breast cancer for beta-D-glucosidase (p less than 0.001). Further, lower differences were found in the patients with acute viral hepatitis for beta-D-fucosidase and alpha-L-fucosidase (p less than 0.01); in acute myocardial infarction for beta-N-acetylglucosaminidase, beta-D-glucosidase, alpha-D-glucosidase, beta-D-fucosidase and beta-D-galactosidase (p less than 0.01, p less than 0.05, p less than 0.05, p less than 0.01 and p less than 0.01, respectively); and in breast cancer for beta-N-acetylglucosaminidase (p less than 0.01). No significant differences were found for the other glycosidases.
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PMID:Serum beta-N-acetylglucosaminidase, beta-D-glucosidase, alpha-D-glucosidase, beta-D-fucosidase, alpha-L-fucosidase and beta-D-galactosidase levels in acute viral hepatitis, pancreatitis, myocardial infarction and breast cancer. 680 Jun 74

Nine lysosomal enzymes and alkaline phosphatase have been assayed in human pancreatic juice from controls and patients with chronic calcifying pancreatitis. Specific activities were evaluated by a nonparametric test (Wilcoxon) with a probability of 2 P less than or equal to 0.5. The values of acid phosphatase, alpha-glucosidase, beta-glucosidase and alpha-galactosidase are significantly higher in pathological juices; the values of alpha-mannosidase and beta-glucuronidase are also increased in the same patients but at the limit of significance. Alkaline phosphatase, beta-hexosaminidase and alpha-fucosidase follows the same trend but the values are not statistically significant between the two groups of patients. Studies on skin cultures of four patients with chronic calcifying pancreatitis demonstrate that the increased specific activities of lysosomal enzymes in the pathological juices do not correspond to a leakage of these enzymes into the extracellular space as described for cystic fibrosis.
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PMID:Alkaline phosphatase and acid lysosomal hydrolases in pancreatic juice and fibroblast cell cultures of patients with chronic calcifying pancreatitis. 680 85

Nine tumour lines with different developmental capacities were derived from spontaneous as well as from one induced teratocarcinoma: three teratocarcinoma-derived rhabdomyosarcomas TDR 602, TDR 694, and TDR 114; two teratocarcinoma-derived neuroblastomas TDN 2151 and TDN 2283; two teratocarcinoma-derived endodermal tumours TDE 274 and TDE 113; one multipotential teratocarcinoma OTT 2289, and one undifferentiated teratocarcinoma OTT 2158. Quantitative analyses of ten catabolic enzymes, i.e. alkaline and acid phosphatase, alpha- and beta-galactosidase, alpha- and beta-glucosidase, alpha-mannosidase, alpha-fucosidase, beta-glucuronidase, and hexosaminidase were carried out at the 20-cell level, and specific enzyme activity profiles were established for each of the tumour lines studied. These profiles may be used for the biochemical identification of a tumour type at the single cell level in addition to morphological and biological criteria.
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PMID:Enzyme activity profiles in mouse teratocarcinomas. A quantitative ultramicroscale analysis. 687 24

We are studying the biosynthesis and processing of acid hydrolases from Dictyostelium discoideum. We prepared antibody to highly purified alpha-mannosidase from the spent medium of stationary phase cultures. It precipitated alpha-mannosidase but not beta-hexosaminidase, alpha-glucosidase, beta-glucosidase, or any of the major proteins in cell lysates or secretions. The antibody precipitated a 150,000- and an 80,000-dalton protein in addition to mature forms (56,000-62,000 daltons) of alpha-mannosidase subunits. The possibility that the 150,000 and 80,000 dalton bands were precursors of mature forms was evaluated by pulse-chase experiments. Following a 20-min pulse labeling period, only the 150,000-dalton protein was detected in the immunoprecipitate. Apparent conversion of this form into 80,000- and 60,000-dalton forms was observed following a 30-min chase. During the next 90 min continued accumulation of 60,000-dalton and appearance of 62,000-dalton forms was observed while the 80,000-dalton form disappeared. The fate of the 150,000-dalton precursor depended on nutritional conditions. In cells conditioned with fresh growth medium intracellular processing predominated. Less than 10% of either the precursor or mature forms was secreted in 8 hr. However, when cells were shifted from growth medium to starvation buffer, secretion of precursor soon predominated. After a 1-hr lag period, cells began secreting 150,000-dalton precursor into the medium. After 4 hr in starvation buffer, the rate of secretion of 150,000-dalton form increased by at least an order of magnitude while processing was markedly diminished. This may be a case where nutritional conditions control the sorting of an acid hydrolase precursor.
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PMID:Processing and secretion of alpha-mannosidase forms by Dictyostelium discoideum. 705 Jan 3


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