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:3.2.1.23 (beta-galactosidase)
14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Changes of activity of several glycosidases (beta-galactosidase, beta-glucuronidase, N-acetyl-beta-D-glucosaminidase, alpha-D-mannosidase and alpha-L-fucosidase) were compared in the forebrain and cerebellum during postnatal development of the rat. Detailed analysis of the data showed similarities, but also substantial differences in their development in both organs. This is interpreted as an indication of the presence of common regulatory mechanisms, as well as of other factors which differently influence development of the glycosidases studied in both CNS parts.
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PMID:Comparison of postnatal development of several acid glycosidases in the rat forebrain and cerebellum. 2 Jan 69

Assay of alpha-L-iduronidase, heparin sulphamidase, N-acetyl-alpha-D-glucosaminidase, arylsulphatase B, alpha-L-fucosidase, beta-glucuronidase, beta-galactosidase and alpha-D-mannosidase in cultured cells is described. Activities in deficient fibroblast strains are compared to control fibroblast strains. The first case of Sanfilippo B in the United Kingdom is reported. A comparison of enzyme activities in cultured fibroblasts and amniotic fluid cells is made.
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PMID:Diagnosis of the mucopolysaccharidoses using cultured skin fibroblasts and amniotic fluid cells. 11 32

K-m values of beta-N-acetylglucosaminidase (2-acetamido-2-deoxy-beta-D-glucoside acetamidodeoxyglucohydrolase EC 3.2.1.30), beta-N-acetylgalactosaminidase (EC 3.2.1.53), beta-galactosidase (beta-D-galactoside galactohydrolase EC 3.2.1.23) and alpha-L-fucosidase (alpha-L-fucoside fucohydrolase EC 3.2.1.51) of distal colonic tumours, induced in rats by 1,2-dimethylhydrazine, were found to be significantly different compared with the values for the enzymes of the colonic mucosa of the control and tumour-bearing animals and of the proximal colonic tumours. The inhibition kinetics data also showed a significant difference between the enzymes of the distal colon tumours and of other experimental tissues. The data on the effect of pH on enzyme kinetics (pK values) showed no significant difference in the catalytic groups of the active centres of enzymes from tumours and from the control colonic mucosa. Tumour beta-N-acetylglucosaminidase and beta-N-acetylgalactosaminidase compared with the enzymes from other experimental tissues were found to be different in their thermal inactivation kinetics. K-m values of 14 days old foetal intestinal beta-N-acetylglucosaminidase and beta-N-acetylgalactosaminidase were significantly different from the values obtained for the adult mucosal enzymes but were similar to those of the distal colonic tumour enzymes.
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PMID:Studies on the kinetics of glycosidases from chemically-induced rat colonic tumours and normal rat colon. 23 55

Several lysosomal enzyme activities in cultured lymphoid cell lines were studied during 3 phases of cell culture; logarithmic growth phase, stationary phase and decline phase. Enzyme induction during cell growth was found in N-acetyl-hexosaminidase, beta-galactosidase and alpha-L-fucosidase, but no induction in alpha-D-mannosidase, alpha-glucosidase and beta-glucuronidase. The latter two enzymes were unchanged during all cell culture phases. A drop in alpha-L-fucosidase and alpha-D-mannosidase activity was found during the stationary and decline phases of cell culture.
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PMID:Lysosomal enzyme activities in cultured lymphoid cell lines. 41 May 67

Human serum alpha-L-fucosidase has been purified 241 200-fold with 35% yield by an affinity chromatographic procedure utilizing agarose-epsilon-aminocaproyl-fucosamine. Isoelectric focusing of the purified enzyme indicated the presence of several forms, with the form at pI 5.0 comprising the majority of the activity. Assay of the purified alpha-L-fucosidase showed only trace amounts of contaminating glycosidases present, with beta-galactosidase being the largest contamnant (0.5% by activity). Sodium dodecyl sulfate polyacrylamide gel electrophoresis indicated the presence of two subunits with very similar molecular weights (56 500 and 54 000). Using the p-nitrophenyl substrate, the purified serum alpha-L-fucosidase has an apparent Michaelis constant of 0.52 mM and a broad pH optimum centered around pH 4.8 with a second, minor optimum at pH 6.1. Gel filtration on Sepharose 6-B indicated an apparent molecular weight of 296 000 +/- 30 000. Preincubation with antibodies made previously against purified liver alpha-L-fucosidase led to quantitative immunoprecipitation of the purified serum alpha-L-fucosidase. Assay of the purified serum alpha-L-fucosidase for sialic acid indicated the presence of 1.7 microgram sialic acid per 100 microgram enzyme, about twice that previously found for the purified liver enzyme.
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PMID:Human serum alpha-L-fucosidase. 61 76

The involvement of glycoconjugates in the insulin-receptor interactions in mouse liver is tested by digestions of membranes with various enzymes. Trypsin decreased the binding of [125I]insulin to liver membranes. After digestion with beta-galactosidase no ""high affinity'' receptor sites could be detected. The effects observed with plant lectins confirm the involvement of galactoconjugates in the insulin binding process. Sophora japonica and Ricinus communis lectins (with galactose specificity) and concanavalin A largely inhibit the binding process of insulin and those effects concern the ""high affinity'' receptor sites. Other lectins (wheat germ agglutinin, Dolichos) and enzymes (alpha-L-fucosidase, beta-N-acetyl-hexosaminidase and neuraminidase) are without effect on insulin binding. Comparative studies performed on diabetic mouse liver membrane (KK mice), previously characterized by decreased number of insulin receptors, are in good agreement with qualitatively similar receptor sites in both non-diabetic (control) and diabetic mice. Effects of enzymes and lectins yielded same results as compared to control membranes. Plasma membrane proteins and glycoproteins in both types of mouse are indistinguishable with respect to enzymic and chemical analysis. Sodium dodecyl sulphate acrylamide gel electrophoresis shows identical patterns. Moreover, the decrease in the number of insulin receptors is easily reversed with diet restriction. These data are consistent with the similarity of receptor sites in control and diabetic liver membrane.
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PMID:Involvement of glycoconjugates in insulin-receptor interactions. Studies in liver plasma membranes of control and diabetic mice. 69 17

Two water-soluble complex carbohydrate storage products were isolated from tissues and urine of patients with an inherited deficiency of lysosomal alpha-L-fucosidase (fucosidosis). The major component was an oligosaccharide of approximate molecular weight 1700, indicating that it was a dekasaccharide. From a combination of sequential digestion with purified exo-glycosidases, periodate oxidation and permethylation in conjunction with gas-liquid chromatography mass spectrometric analysis, the structure was found to be: Fuc(alpha 1 leads to 2)Gal-(beta 1 leads to 4) GlcNAc (beta1 leads to 2)Man [Fuc(alpha1 leads to 2) Gal (beta1 leads to 4) GlcNAc(beta1 leads to 2) Man] (alpha 1 leads to 3/6) Man (beta1 leads to 4) GlcNAc, although there was some evidence for heterogeneity at the mannose branchpoint. This material is structurally related to the stored oligosaccharides in patients with inherited deficiencies of beta-galactosidase (G M1-gangliosidosis) and N-acetyl-beta-hexosaminidase (G M2-gangliosidosis). A dissaccharide with the probable structure Fuc(alpha1 leads to 6)GlcNAc was found in lesser amounts in tissues; both are believed to be derived from the impaired catabolism of large numbers of different glycoproteins.
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PMID:Structure of the accumulating oligosaccharide in fucosidosis. 97 44

KB cells were synchronized by a double thymidine block procedure. An investigation was made of the activities of alpha-L-fucosidase (EC 3.2.1.51), alpha-D-galactosidase (EC 3.2.1.22), beta-D-galactosidase (ec 3.2.1.23), alpha-D-glucosidase (EC 3.2.1.20), beta-D-glucosidase (EC 3.2.1.21), alpha-D-mannosidase (EC 3.2.1.24), beta-D-N-acetylgalactosaminidase (EC 3.2.1.53), and beta-D-N-acetylglucosaminidase (EC 3.2.1.52) from synchronized cultures, using appropriate artificial substrates. Ceramide glucosidase (EC 3.2.1.45) and ceramide trihexosidase levels (EC 3.2.1.47) were also investigated at various stages in the cell cycle, using appropriate glycosphingolipid substrates. Whereas each of these enzymes exhibited some activity throughout the cell cycle, peak activity (2- to 6-fold increase) occurred late in the S phase. Two molecular forms of ceramide glucosidase (optimal activity at pH 4.0 and pH 6.0) and two forms of ceramide trihexosidase (pH 4.0 and pH 7.5) were identified. Peak levels of the forms that preferred the relatively acid pH occurred earlier in the S phase of the cell cycle than those of the forms that were more active at the higher pH. The possibility that the forms with optimal activity at pH 4 are precursors of those with optimal activity at pH 6 to 7.5 is discussed. Precipitation of beta-galactosidase of synchronized KB cells with specific antibody revealed that changes in the activity of this enzyme during the cell cycle were the result of fluctuations in the amount of the enzyme.
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PMID:Glycosphingolipid glycosyl hydrolases and glycosidases of synchronized human KB cells. 115 Jun 49

Impact of altered serum prolactin status on enzymes involved in glycoprotein metabolism in epididymal tissue of matured monkeys was studied. Hyperprolactinemia (ovine prolactin-250 micrograms/kg body weight/day for 30 days) significantly inhibited the specific activities of dolichylphosphate mannosyl transferase, dolichylphosphate glucosyl transferase and galactosyl transferase, in the epididymal tissues. However, it had an enhanced effect on epididymal glycosidases such as beta-galactosidase, beta-N-acetyl glucosaminidase, beta-N-acetyl galactosaminidase, alpha-mannosidase and alpha-L-fucosidase. Hypoprolactinemia (bromocriptine mesylate-1-mg/kg body weight/day for 30 days) on other hand had no significant effect on the specific activities of both, glycosyltransferases and glycosidases, in the epididymal tissues. The results suggest that hyperprolactinemia inhibits epididymal glycoprotein metabolism by impairing the incorporation of oligosaccharide units into proteins with enhanced degradation. This may have adverse effect on events leading to sperm maturation in epididymal environment.
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PMID:Role of prolactin on epididymal glycoprotein metabolism in matured monkeys, Macaca radiata: specific activities of glycosyltransferases and glycosidases. 129 32

Several lysosomal enzymes present in human plasma (N-acetyl-beta-glucosaminidase, beta-glucuronidase, beta-galactosidase, alpha-galactosidase, alpha-L-fucosidase, alpha-mannosidase, beta-glucosidase) were maintained in a fully active state for at least 8 months by the addition of ethylene glycol (300 milligrams final concentration) to freshly prepared plasma and storage at -20 degrees C. Pools of human plasma from healthy humans, stabilized and stored as above, and containing a low, medium or high content of the above enzymes, were used to establish the analytical imprecision (within-run, day-to-day and total imprecision) of the fluorimetric assay. Ten replicates in ten different analytical series, covering a period of two months, were performed. The total imprecision (expressed as coefficient of variation) was in general lower than 10%; in a few cases, particularly plasma samples with a low enzyme content, the total imprecision was 18%. The isozymes A, B, I1, and I2 of N-acetyl-beta-glucosaminidase displayed the same stability upon storage as the unfractionated enzyme. It is concluded that pools of human plasma containing known amounts of lysosomal enzymes, stabilized by the addition of 300 micrograms ethylene glycol and stored at -20 degrees C, are suitable liquid materials for calibration and quality control for the assay of the same enzymes.
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PMID:Preparation of a stable liquid material for calibration and quality control for lysosomal enzymes in plasma. Assay of enzymes of lysosomal origin in plasma, I. 133 72


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