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)

The purpose of the present study was to determine the role of cardiac lysosomal enzymes in the pathogenesis of the cardiomyopathy that develops in the genetically diabetic C57BL/KsJ db+/db+ mice. Db+/db+ mice and littermate controls were sacrificed as age-matched pairs between 5 and 26 weeks of age. C57BL/6J ob/ob mice and littermates served as other controls. Following anesthesia, the hearts were excised, homogenized, and the following enzymatic activities measured: N-acetyl-beta-glucosaminidase, N-acetyl-beta-galactosaminidase, beta-glucosaminidase, aryl sulfatase, alpha-mannosidase, alpha-glucosidase, beta-galactosidase, beta-glucosidase, total rho-nitrophenyl phosphatase, acid phosphatase. and 5'-phosphodiesterase type IV. There is a progressive decrease in cardiac lysosomal enzyme activities of db+/db+ mice for the period 5 to 21 weeks of age. All enzyme activity is depressed significantly during the 9- to 21-week interval: alpha-glucosidase, beta-glucosidase, alpha-mannosidase, beta-galactosidase, acid phosphatase, N-acetyl-beta-galactosaminidase, 5'-phosphodiesterase type IV, and total rho-nitrophenyl phosphatase are reduced approximately 10 to 20 per cent, whereas beta-glucosaminidase, aryl sulfatase, and N-acetyl-beta-glucosaminidase are decreased almost 40 to 50 per cent. In contrast, cardiac lysosomal enzymic activity in the ob/ob mice does not differ significantly from controls aside from aryl sulfatase (20 per cent decrease) and beta-glucosidase (10 per cent decrease). This decrease in lysosomal enzyme activity can explain the accumulation of large residual bodies and interstitial material that occurs in the myocardium of the db+/db+ animals as part of the cardiomyopathy.
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PMID:Lysosomal enzymes in the heart of the genetically diabetic mouse. 742 Nov 26

Beta-N-Acetylglucosaminidase has been purified from an acetone extract of Aspergillus niger. The protein has a Mr = 149,000. It contains neither Mn2+, Zn2+, nor cysteine and exhibits no cation requirement for activity. Isoelectric focusing separates two isozymes; the major isoenzyme has a pI = 4.4. Both isozymes exhibit beta-N-acetylgalactosaminidase and beta-glucosidase, as well as glucosaminidase activity. The mechanism of action of this enzyme has been studied in detail using a variety of substrate structure/activity and kinetic experiments. Rate data plotted versus pH depends on the following ionization constants, respectively: for pKm, 2.95; for log Kcat, 7.6; and for log kcat/Km, 2.95 and 8.25. The kcat value of H2O/D2O for p-nitrophenyl-beta-N-acetylglucosaminide hydrolysis is 1.27 at pH 4.6 and 1.00 at pH 7.0. The rho value for the hydrolysis of para-substituted phenylglucosaminides is +0.36; rho for the hydrolysis of fluoro-substituted N-acetyl derivatives is -1.41. Two sulfur-containing substrate analogues, the 1-thioglucosaminide, and the N-thioacetyl derivative, exhibit either no or little substrate activity. The hydrolysis of the 2,4-dinitrophenyl-glucosaminide is not biphasic as indicated by stopped flow kinetic studies. These several results are interpreted to show that: 1) enzymatic nucleophilic catalysis is not employed by beta-N-acetylglucosaminidase; 2) the glycosidic oxygen is protonated very early in the reaction, perhaps even in the Michaelis complex; 3) the acetamido oxygen provides anchimeric assistance to hydrolysis via charge stabilization of the oxocarbonium ion (or via oxazoline formation); 4) additional charge stabilization is provided by an enzymic anion, perhaps a side chain carboxylate group. The role of the acetamido group is discussed and comparisons are made between lysozyme, beta-galactosidase, and beta-N-acetylglucosaminidase.
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PMID:Purification, properties, kinetics, and mechanism of beta-N-acetylglucosamidase from Aspergillus niger. 744 May 73

Morphological and histoenzymological differences have been observed between intercalated and principal cells of the quail Coturnix coturnix japonica collecting ducts. The present study was designed to shed light on the lectin affinity of the collecting duct cells within cortex and medulla by the use of HRP-labelled lectins combined with glycosidase degradation. Binding of PNA and RCA-I lectins consequent to enzymatic release of sialic acid revealed abundant sialylated carbohydrate moieties within the principal cell cytoplasm. This characteristic binding pattern differed considerably from the staining observed in the intercalated cells. Interesting information also emerged about the presence of sialoglycoconjugates having the terminal disaccharide sialic acid-beta-N-acetylgalactosamine originating from the increased SBA binding and the unmodified DBA labelling after removal of sialic acid. Sequential degradation by sialidase/beta-galactosidase followed by incubation with DBA offered the possibility to suspect that the receptor sugar for the penultimate beta-galactose may be N-acetylgalactosamine. Conversely, we were not able to define the accept sugar for penultimate beta-GalNAc owing to the lack of availability of beta-N-acetylgalactosaminidase enzyme. When although further studies are clearly needed to elucidate the physiological role of the cellular sialoglycoconjugates detected, the present results already provide valuable insight into the carbohydrate composition of intercalated and principal cells in the quail collecting ducts.
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PMID:Mosaic lectin labelling in the quail collecting ducts. 754 Dec 64

The importance of bacterial vaginosis as a risk factor in obstetric and gynecological infections has recently been recognized. The bacterial vaginosis group of organisms includes members of the Streptococcus milleri group, the identification of which has caused much confusion. We prospectively surveyed the rates of carriage of S. milleri group organisms in 397 high vaginal swabs received in our laboratory. For the identification of 99 clinical isolates and 23 control strains, we compared the results obtained by the rapid ID 32 Strep system (Analytab Products) and by a scheme utilizing six differential phenotypic characteristics (presence of beta-N-acetylglucosaminidase, alpha-glucosidase, beta-D-fucosidase, beta-galactosidase, beta-N-acetylgalactosaminidase, and beta-glucosidase) as described by Whiley et al. (R. A. Whiley, H. Fraser, J. M. Hardie, and D. Beighton, J. Clin. Microbiol. 28:1497-1501, 1990). We identified Streptococcus anginosus in 18% and Streptococcus constellatus in 0.05% of the specimens examined. Of the isolates of S. anginosus that reacted with grouping antisera, 20 of 25 belonged to Lancefield group F. The incubation conditions for bacterial cultures and for reaction mixtures affected the results of phenotypic characterization in the production of alpha-glucosidase, beta-galactosidase, and beta-glucosidase. However, by using bacterial cultures grown under hypercapnic conditions and incubating the reaction mixtures aerobically, consistent phenotypic characteristics were obtained, allowing identification similar to that obtained by the ID 32 Strep system. We therefore recommend the phenotypic scheme as an inexpensive, reliable, and convenient method for the initial identification of species of the S. milleri group.
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PMID:Species identification of members of the Streptococcus milleri group isolated from the vagina by ID 32 Strep system and differential phenotypic characteristics. 765 Jan 93

Four different insect cell lines that can be used as hosts for baculovirus infection were assayed for the presence of endogenous exoglycosidases. All four cell lines, derived from Spodoptera frugiperda, Trichoplusia ni, Bombyx mori, or Malacosoma disstria, contained N-acetyl-beta-glucosaminidase, N-acetyl-beta-galactosaminidase, beta-galactosidase, and sialidase activities. Exoglycosidase activities were found in cell lysates as well as cell-free supernatants from uninfected and wild-type baculovirus infected cells. Oligosaccharide analysis of cellular glycoproteins using lectins recognizing Gal beta 1, 3GalNAc, Gal beta 1, 4GlcNAc, and NeuAc alpha 2,6Gal demonstrated that only Gal beta 1,3GalNAc was present. The demonstration that these cells contain exoglycosidases raises the possibility that the oligosaccharides of baculovirus-expressed glycoproteins are subject to enzymatic degradation.
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PMID:Insect cell hosts for baculovirus expression vectors contain endogenous exoglycosidase activity. 776 90

The characterization and properties of a beta-galactanase and alpha- and beta-galactosidases as well as heparan sulfate and chondroitin sulfate degrading enzymes which appear during the 15 days of the embryonic development of the mollusc Pomacea sp. is reported. The beta-galactanase, which appears around day 7 of development, was separated from alpha- and beta-galactosidase which emerge at day 1 and 4 after oviposition, respectively. The galactanase seems to be responsible for the degradation of an acidic beta-galactan (which is also synthesized by the eggs around day 5) to galactose and di- and tri-galactosides. Heparan sulfate appears around day 10 of development together with a heparan sulfate endoglucuronidase responsible for the degradation of its N-acetylated region. An alpha-N-acetylglucosaminidase and a beta-glucuronidase which act upon the N-acetylated fragments formed from heparan sulfate emerge around day 4 of development. Chondroitin sulfate and a chondroitin sulfate sulfatase emerge around day 9 of development whereas a beta-N-acetylgalactosaminidase and the beta beta-galactan, heparan and chondroitin sulfate, respectively. The possible role of these elements in the migration of mesenchymal cells, in the processes of cell-cell recognition and control of cell growth is discussed.
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PMID:Appearance and fate of a beta-galactanase, alpha, beta-galactosidases, heparan sulfate and chondroitin sulfate degrading enzymes during embryonic development of the mollusc Pomacea sp. 806 9

Of the 29 'Streptococcus milleri' strains tested, all thirteen Streptococcus intermedius (DNA homology group 2) strains but none of the thirteen Streptococcus anginosus (group 1) strains produced beta-N-acetylglucosaminidase, beta-N-acetylgalactosaminidase, alpha-N-acetylneuraminidase, beta-galactosidase, alpha-glucosidase, and hyaluronidase. The three Streptococcus constellatus (group 3) strains produced only the latter two. Glycosidase production divided 274 clinical isolates into 103 S. anginosus, 101 S. intermedius, and 70 S. constellatus strains. Generally, strains of S. anginosus and S. intermedius were non-beta-haemolytic. API II and biotype Ia (lactose positive), but the former contained almost all API III strains and belonged to Lancefield group A/serotype a (A/a), -/b, C/c, -/d, -/e, F/f or G/k, and the latter included most of biotype IId (lactose negative) and serovar -/g, -/h, -/i or -/j. S constellatus strains were beta-, alpha- or gamma-haemolytic, of API I or II but mostly biotype Ib (lactose negative), and of F/- or -/b. S. intermedius was a major member of the oral isolates. Non-oral isolates were virtually all S. anginosus (mainly urogenital isolates) or S. constellatus (the other systemic isolates).
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PMID:Enzymatic differentiation and biochemical and serological characteristics of the clinical isolates of Streptococcus angiosus, S. intermedius and S. constellatus. 829 53

The purpose of the present paper was to study the effects of a dietary undigestible carbohydrate and intestinal microflora on mucin distribution (neutral, acid, sulphonated), glycolytic activities: beta-D-galactosidase (EC 3.2.1.23), N-acetyl-beta-D-galactosaminidase (EC 3.2.1.43), N-acetyl-beta-D-glucosaminidase (EC 3.2.1.30), alpha-L-fucosidase (EC 3.2.1.51) and bacterial metabolism (gas production, short-chain fatty acids (SCFA) and lactic acid caecal concentration) in germ-free (GF), conventional (CV) and heteroxenic (HE) rats (GF rats associated with a human flora). Rats were fed on either a control diet or a diet containing 40 g trans-galactosylated oligosaccharide (TOS)/kg. In GF rats fed on the control diet caecal pH was almost neutral and glycolytic activities negligible. The number of mucus-containing cells increased from the caecum to the colon for the three types of mucin. TOS had no effect in the caecum but it modified mucin cell repartition in the colon. In CV and HE rats fed on the control diet caecal pH was similar (6.8), but caecal SCFA and lactic acid concentrations (mumol/g) and gas production (ml/24 h) were higher in CV (70, 5.9 and 2.3 respectively) than in HE rats (32, 4.6 and 0.4 respectively). In CV, as in HE rats, acid-mucin-containing cells increased from the caecum to the colon and glycolytic activities were similar. TOS reduced acid-mucin-containing cells in the caecum of CV rats by twofold but had no effect in either the caecum or the colon of HE rats. TOS strongly increased beta-galactosidase activity and slightly modified the other glycolytic activities. Its effect on bacterial metabolites depended on bacterial status. However, comparison between CV and HE rats showed no evident relationship between the number of mucus-containing cells and measured bacterial metabolites. Differences between CV and HE rats might be due to bacterial microflora specificity. TOS had an intrinsic effect on mucus cell distribution in the colon of GF rats. In CV and HE rats the presence of the flora abolished this effect.
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PMID:Effects of galacto-oligosaccharide and bacterial status on mucin distribution in mucosa and on large intestine fermentation in rats. 832 64

The impact of hyper- and hypothyroidism on prostatic glycosidases was investigated. Hyper-thyroidism was induced by administering L-thyroxine (25 micrograms/100 g body weight/day) for 60 days and hypothyroidism was induced by total thyroidectomy. To test the direct influence of thyroid hormones, prostatic lobes were incubated with different concentrations (10, 25 and 50 ng/mL) of T3 and beta-N-acetylglucosaminidase and beta-N-acetylgalactosaminidase were assayed. Serum levels of thyroid hormones, oestradiol and testosterone increased in hyperthyroid, and decreased in hypothyroid rats. TSH decreased in hyperthyroid, and an opposite trend was seen in thyroidectomized, rats. Prostatic [anterior (coagulating glands), dorsolateral and ventral prostates] beta-glucosidase, beta-galactosidase, beta-N-acetylglucosaminidase and beta-N-acetylgalactosaminidase activities increased uniformly in hyperthyroid, and decreased in thyroidectomized, rats. In vitro studies showed a dose-dependent stimulatory effect of T3 on beta-N-acetylglucosaminidase and beta-N-acetylgalactosaminidase in all three lobes of the prostate. From the present study, it is concluded that hyperthyroidism augments and hypothyroidism inhibits prostatic glycosidases and T3 has a direct stimulatory effect on these enzymes.
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PMID:Impact of altered thyroid hormone status on prostatic glycosidases. 966 96

The impact of hyperthyroidism on epididymal glycosidases was studied in albino rats. Hyperthyroidism was induced in Wistar rats aged 30 days by daily injection of T4 (25 microg/100 g body weight/day intramuscularly) for 30 or 60 days; control rats were injected with vehicle (alkaline saline, pH 7.8). One set of hyperthyroid rats was reverted to euthyroid status by withdrawing T4 treatment after 30 days of hyperthyroidism. To asses the direct effect of thyroid hormone on epididymal hexosaminidases, caput, corpus and cauda tissues were stimulated with 25, 50 or 100 ng/mL T3 for 24 h, after an initial culture of 24 h. The activity of beta-glucosidase decreased in caput, corpus and cauda epididymis of hyperthyroid rats. beta-Galactosidase activity increased in the caput epididymis irrespective of the duration of hyperthyroidism. While a similar decrease occurred in the corpus and cauda epididymis in the 30 day hyperthyroid group, an opposite trend was observed in 60 day hyperthyroid rats. Caput beta-N-acetylglucosaminidase activities increased at both time points, whereas activity decreased in the corpus and cauda in 30 day, but increased in 60 day hyperthyroid rats. Hyperthyroidism consistently increased caput and corpus beta-N-acetylgalactosaminidase activity irrespective of the duration. Cauda epididymal beta-N-acetylgalactosaminidase activity was decreased in 30 day and increased in 60 day hyperthyroid rats. Hyperthyroidism induced changes in caput beta-galactosidase, beta-N-acetylgalactosaminidases, corpus beta-N-acetylglucosaminidase and cauda beta-N-acetylgalactosaminidase which were irreversible while the remaining actvities were brought back to normal when T4 treatment was withdrawn. In vitro studies showed that T3 stimulates epididymal hexosaminidases (beta-N-acetylglucosaminidase and beta-N-acetylgalactosaminidase) irrespective of the dose. These data suggest that thyroid hormones have a specific and direct influence on glycosidases in specific regions of the epididymis.
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PMID:Differential effect of hyperthyroidism on rat epididymal glycosidases. 1145 72


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