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)

Enzymatic degradation followed by lectin application was carried out on specimens of the rabbit oviduct. The sequential application of the glycosidases (neuraminidase, alpha-L-fucosidase, beta-galactosidase and alpha-mannosidase) and lectins (peanut, winged pea, wheat germ and soybean) seem promising as an effective method for characterising, in situ, the structure of complex carbohydrate chains. The data obtained after digestion with neuraminidase and alpha-L-fucosidase indicate the presence of a continuous layer of sialoglycoconjugates and fucoglycoconjugates that completely covers the luminal surfaces of the ampulla. The different reactivity of the glycocalyx and the secretory products indicates a different chemical composition of glycoconjugates in the glycocalyx and secretions. Although it is very difficult to explain the lectin affinity and the functional significance of the positive cells, some hypotheses have been advanced.
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PMID:Characterisation in situ of the complex carbohydrates in rabbit oviduct using digestion with glycosidases followed by lectin binding. 407

In the newborn lamb, activities of lysosomal enzymes are lower in the duodenum and jejunum than in the ileum. In contrast, there are only minor differences, if any, in activities of lysosomal enzymes between the regions of the small intestine of 5-day-old lambs. In the duodenum, jejunum and ileum, activities of hexosaminidase, alpha-mannosidase, beta-mannosidase, alpha-L-fucosidase and phosphodiesterase are greater in newborn than in 5-day-old lambs. Only in the distal part of the small intestine are activities of beta-glucuronidase, alpha-glucosidase, alpha-galactosidase, beta-galactosidase, acid phosphatase and cathepsin B higher in the newborn than in 5-day-old lambs. Cathepsin B activity is lower in the duodenum and jejunum of the newborn than in 5-day-old lambs.
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PMID:Lysosomal enzymes in the intestine of the newborn lamb. 609 93

The following enzymes of lysosomal origin were fluorimetrically determined in maternal plasma from the second to the ninth month of pregnancy at 1-mth intervals: beta-D-N-acetylglucosaminidase (EC 3.2.1.30), beta-D-glucuronidase (EC 3.2.1.31), beta-D-glucosidase (EC 3.2.1.21), beta-D-galactosidase (EC 3.2.1.22), alpha-D-galactosidase (EC 3.2.1.23), alpha-L-fucosidase (EC 3.2.1.51) and alpha-D-mannosidase (EC 3.2.1.24) (pH 4.0). As reference microsomal alpha-D-mannosidase (pH 5.7) was also studied. Thirty-eight healthy women, aged 18-37 yr, who had a normal pregnancy followed by normal parturition, were studied. All enzymes, with the only exception of beta-D-galactosidase, showed a progressive and statistically significant increase of activity throughout pregnancy. At the end of pregnancy, the increase ranged from a maximum of 5.6-fold for beta-D-N-acetylglucosaminidase to a minimum of 0.55-fold for alpha-D-mannosidase, pH 5.7. In the case of beta-D-N-acetylglucosaminidase, the level at the fifth month of pregnancy was significantly higher than that at the third month, and from the sixth to the ninth month each level significantly differed from that of the month immediately preceding.
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PMID:Behaviour of several enzymes of lysosomal origin in human plasma during pregnancy. 609 42

Six glycosidase activities were detected in homogenates of the rat uterus by using the p-Nitrophenyl-glycoside as substrate. The enzyme activities were separated by Sephadex G-200 column chromatography. The uterus contained alpha-galactosidase, beta-galactosidase and N-acetylglucosaminidase activity which had a similar pH optima of 4.4, whereas the pH optimum for beta-fucosidase was found to be of 4.4 - 4.6. The alpha-mannosidase activity showed two peaks of maximal activity at pH 5.0 and pH 6.0. The uterus contained two forms of the alpha-L-fucosidase activity separable by Sephadex G-200 which had a pH optima of 4.4 - 4.6 (form I) and pH 5.0 (form II). The glycosidases differed in heat stability, Km values and other several characteristics, which suggests that each enzyme apparently did not show any cross-contamination.
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PMID:Glycosidases from the rat uterus. 609 87

Coated vesicles from calf brain and rat liver contain cryptic receptors which recognize and bind lysosomal enzymes via mannose 6-phosphate residues on oligosaccharide side chains (Campbell, C. H., Fine, R. E., Squicciarini, J., and Rome, L. H. (1983) J. Biol. Chem. 258, 2628-2633). In addition to mannose 6-phosphate receptors, we now report that coated vesicles from calf brain and rat liver contain the lysosomal enzymes alpha-L-fucosidase, beta-galactosidase, beta-glucosidase, beta-hexosaminidase, alpha-L-iduronidase, and alpha-mannosidase. Enzyme activities co-migrated with coated vesicles purified by agarose gel electrophoresis. Treatment of intact coated vesicles with pronase (0.05 mg/ml) had little effect on lysosomal enzyme activities, whereas a similar treatment of coated vesicles in the presence of 0.045% taurodeoxycholate resulted in the loss of most of the enzyme activities. Addition of 10 mM mannose 6-phosphate to disrupted liver coated vesicles specifically displaced up to 80% of the cryptic lysosomal enzyme activity. Disrupted liver coated vesicles and highly purified liver lysosomes were treated with anti-beta-hexosaminidase A and anti-beta-galactosidase antibodies and immunoprecipitates were analyzed by polyacrylamide gel electrophoresis. High molecular weight bands were present in the coated vesicle immunoprecipitates which were not present in the lysosome immunoprecipitates. The data suggest that coated vesicles contain mannose 6-phosphate receptor-bound lysosomal enzymes, some of which are of a higher molecular weight form. These higher molecular weight forms may represent newly synthesized enzymes that are en route to lysosomes.
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PMID:Coated vesicles from rat liver and calf brain contain lysosomal enzymes bound to mannose 6-phosphate receptors. 613 57

beta-Galactosidase, alpha-D-mannosidase, alpha-L-fucosidase and N-acetyl-beta-D-glucosaminidase activities were assayed in serum and urine from rats treated with three different doses of the nephrotoxic antibiotic tobramycin (100 mg/kg/day for 5 days, 10 mg/kg/day for 10 days and 5 mg/kg/day for 20 days) and gentamicin (100 mg/kg/day for 5 days). A significant increase of beta-galactosidase, N-acetyl-beta-D-glucosaminidase and alpha-L-fucosidase activities occurred in urine following the administration of high doses of antibiotic. The enzyme activity was dependent on the dose level used. The excretion of alpha-D-mannosidase was atypical and elevated activities were observed on some days but no pattern of excretion of this enzyme was established. No change in any of the four glycosidase activities was found in serum of treated rats. The results obtained when high doses of gentamicin were employed are similar to those obtained with a similar dose of tobramycin. These results indicate that the assay of urinary glycosidase activities provides a useful method for monitoring the nephrotoxicity of antibiotics.
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PMID:Effect of tobramycin and gentamicin on the activity of some glycosidases in rat serum and urine. 615 73

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 role of carbohydrates in thyrotropin binding was studied by glycosidase treatment of human thyroid membranes. Removal of over 75% of membrane sialic acid resulted in a 50% increase of TSH binding, measured in 10 mM Tris-HCl, 50 mM NaCl, 0.1% bSA, pH 7.4, 37 degrees C (buffer A). This augmentation was due to an increase in binding to high affinity sites (Ka 1 X 10(10)M-1). The binding was highly specific and was not significantly inhibited by gangliosides. In contrast, low affinity binding of TSH was unchanged either in buffer A or in 10 mM Tris-acetate, 0.1% bSA pH 6.0, 4 degrees C (buffer B) and was inhibited by gangliosides. Treatment of membranes with beta-galactosidase, beta-N-acetylglucosaminidase and alpha-L-fucosidase had little effect on TSH binding. The data suggests that membrane-associated sialic acid inhibits TSH binding to high affinity receptors and that gangliosides are not involved in tthis TSH-receptor interaction.
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PMID:Role of carbohydrates in thyrotropin binding sites. 624 6

Six glycoside hydrolases in the culture medium of Bacteroides fragilis--alpha-glucosidase, beta-glucosidase, alpha-galactosidase, beta-galactosidase, beta-N-acetylglucosaminidase, and alpha-L-fucosidase-were systematically purified by ammonium sulfate precipitation, gel filtration chromatography, and density gradient isoelectric focusing. The isoelectric focusing resolved the glycosidases into distinct, well-separated fractions and revealed three differently charged forms of beta-N-acetylglucosaminidase and of alpha-L-fucosidase. Furthermore, alpha-glucosidase and beta-N-acetylglucosaminidase were shown to possess dual affinities for the respective galactoside substrates, and beta-galactosidase also hydrolyzed beta-D-fucoside. alpha-Glucosidase was purified to homogeneity, as indicated by a thin-layer isoelectric focusing zymogram technique. The glycosidases, with exception of beta-glucosidase and the acid alpha-L-fucosidase, were each separated from other glycosidic activities to 99%. The molecular weights varied between 58,000 and 125,000. The pH optima ranged from 4.8 to 6.9.
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PMID:Purification of glycoside hydrolases from Bacteroides fragilis. 625 Apr 77

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


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