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)

1. Chicken brain arylsulphatase A was purified 2000-fold, with overall recovery 14%, by using ammonium sulphate fractionation, ethanol precipitation, Sephadex G-200 gel filtration and DEAE-Sephadex column chromatography. 2. The purified preparation was free from beta-glucuronidase, beta-galactosidase, acid phosphatase, inorganic pyrophosphatase and adenosine 3'-phosphate 5'-sulphatophosphate sulphohydrolase activities. 3. Polyacrylamide-gel electrophoresis indicated that the purified preparation was not homogeneous. 4. Chicken brain arylsulphatase was markedly inhibited by carbonyl reagents in the presence of traces of Cu(2+) in the system. Other metal ions such as Fe(2+) and Zn(2+), were inactive. 5. Ascorbic acid alone had no effect on enzyme activity but enhances the inhibition by Cu(2+). 6. Chicken brain arylsulphatase A resembled arylsulphatase A of other animal species in its kinetic properties such as K(m) value, anomalous time-activity relationship and the inhibitory effect of phosphate, sulphite and sulphate ions. However, its electrophoretic mobility, behaviour under zinc acetate fractionation and stimulation by Ag(+) were similar to arylsulphatase B of other animal species. Thus, this enzyme did not correspond to either arylsulphatase A or arylsulphatase B but properties of both. 7. The purified enzyme preparation can degrade cerebroside 3-sulphate.
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PMID:Purification and properties of arylsulphatase A from chicken brain. 507 33

1. The presence of beta-galactosidase (EC 3.2.1.23) in an acetic acid extract of ram testis is reported. Some properties of the crude enzyme preparation were studied. 2. The purification of beta-acetylglucosaminase (EC 3.2.1.30) and of beta-galactosidase from the ram-testis extract by ammonium sulphate precipitation and chromatography on a CM-cellulose column is described. 3. The final purifications of the separated enzymes achieved were for the beta-acetylglucosaminase 35 times and for the beta-galactosidase 99 times. 4. The possibility of using DEAE-cellulose and Sephadex G-200 to purify the enzymes was investigated.
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PMID:Purification of beta-acetylglucosaminase and beta-galactosidase from ram testis. 594 69

beta-Galactosidase of Streptococcus lactis 7962 was partially purified, and its properties were studied. Enzyme from only this strain of numerous lactic streptococci tested was stable in cell exudates prepared by various means. Cell-free extracts of the 7962 strain were prepared by sonic treatment of washed cells previously grown in presence of lactose to fully induce enzyme synthesis. Protamine sulfate precipitation of the nucleic acids and ammonium sulfate precipitation of protein were used for partial purification of the enzyme. The resulting enzyme, when resuspended in cold (5 C) phosphate buffer, was extremely labile. However, ammonium sulfate in high concentrations (0.85 m) stabilized and stimulated beta-galactosidase activity. Sephadex G-200 gel filtration was used to achieve further purification and to monitor homogeneity of the enzyme. Separation of the beta-galactosidase in buffer at 5 C yielded an enzyme elution pattern showing two peaks of activity. However, addition of the enzyme solution in 0.85 m ammonium sulfate to the column equilibrated with the same salt concentration yielded only one peak of enzyme activity. The data suggested that the native enzyme was dissociating into active subunits which were stabilized in the presence of the ammonium sulfate.
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PMID:Purification and properties of Streptococcus lactis beta-galactosidase. 602 31

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 immature sugar cane stalks studied contained less than 7% sucrose, and showed the activities of enzymes such as invertase, alpha-galactosidase, alpha-mannosidase, beta-N-acetylglucosaminidase, beta-glucosidase, beta-xylosidase, and beta-galactosidase. The alpha-galactosidase was highly purified by ammonium sulfate fractionation, gel filtration on a Sephadex G-100 column, ionexchange chromatography on DEAE-cellulose, and CM-cellulose columns, and heat treatment (60 degrees C, 15 min) in the presence of 0.2 m D-galactose. In polyacrylamide gel electrophoresis, the purified enzyme was homogeneous, having a molecular weight of approximately 46,000. In gelfiltration, it was approximately 47,000. The activity was optimum at pH 4.5 and at 60 degrees C. The purified enzyme hydrolyzed p-nitrophenyl-alpha-D-galactopyranoside (Km, 0.83 mM; Vmax, 25.0 mumol/mg/min), raffinose (Km, 25.9 mM; Vmax, 15.4 mumol/mg/min), and stachyose (Km, 13.0 mM; Vmax 2.7 mumol/mg/min), in addition to melibiose, guar gum, and locust bean gum. The hydrolysis of p-nitrophenyl-alpha-D-galactopyranoside was markedly inhibited by HgCl2, AgNO3, p-chloromercuribenzoate (PCMB), L-ascorbic acid, melibiose, stachyose, and D-galactose. Also the purified enzyme showed a lectin activity with trypsinized erythrocytes.
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PMID:Purification and properties of alpha-galactosidase from immature stalks of Saccharum officinarum (sugar cane). 627 79

Structural studies are reported on seven hybrid proteins produced by gene fusions that contain a "foreign" amino acid sequence substituting for part of the NH2-terminal region of the beta-galactosidase polypeptide. All of these hybrid proteins retain beta-galactosidase enzyme activity. A simple and rapid purification scheme for the hybrid beta-galactosidase is described, involving ammonium sulfate fractionation, DEAE-Bio-Gel, and Bio-Gel A-1.5 chromatography. The proteins are tetramers and have activity equivalent to that of wild type enzyme. Their amino acid sequences were determined by isolation and sequence determination of the cyanogen bromide peptide containing the joining site. The subunit sizes vary from 1009 to 1355 residues compared to 1023 for wild type. Up to 26 amino acid residues at the NH2 terminus of beta-galactosidase can be substituted by the new sequence. The nature of the new sequence apparently has no influence on stability or activity of the hybrid, but those hybrids with more of the beta-galactosidase sequence deleted are less stable to heat or urea treatment and tend to dissociate to dimeric form. All hybrids are less stable to heat and urea than wild type. Antipeptide antibodies raised against peptides derived from the NH2-terminal region of wild type beta-galactosidase were found to bind to the hybrid proteins, although they do not bind to the normal enzyme. These results indicate that the quaternary structure is disturbed but not disrupted by substitution of the different sequence, and these results help to localize one of the intersubunit contact regions in beta-galactosidase.
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PMID:Purification, structure, and properties of hybrid beta-galactosidase proteins. 641 39

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

In search of a beta-galactosidase which specifically hydrolyses beta 1----3 bound galactose residues in galacto-glycoconjugates, an acid beta-galactosidase from chicken liver was investigated. The isolation procedure involved ammonium sulphate precipitation followed by lectin chromatography on Con A-Sepharose 4B, ion-exchange chromatography on DEAE-cellulose, gel filtration on Sepharose 6B and affinity chromatography on p-aminophenyl-thio-beta-D-galactoside-agarose. The beta-galactosidase was purified 3000-fold with 11% recovery of enzyme activity. The purified protein showed an apparent molecular mass of above 200000 in SDS-polyacrylamide gel electrophoresis. A few minor bands were also present. The reduced and denatured beta-galactosidase migrated as a single major band with an apparent molecular mass of 67000. The enzyme released galactose from lactose and from the synthetic substrates Gal beta 1----3Gal, Gal beta 1----6Gal and Gal beta 1----3Ara. However, the enzyme did not release galactose from the snail gland galactans and the high molecular weight galacto-glycoconjugates and it did not hydrolyse the peanut agglutinin receptor of the red blood cell membrane.
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PMID:Isolation of a beta-galactosidase from chicken liver. 644 30

The factor(s) derived from fibrosarcoma-induced suppressor T cells was sensitive to pronase and neuraminidase, but not to trypsin, beta-galactosidase, DNase, or RNase. Protein and RNA, but not DNA, synthesis were required to mediate suppression. Suppressor T cell-derived factor(s) could be precipitated by a 50% saturated ammonium sulfate (SAS) solution. The 50% SAS fraction inhibited both in vitro and in vivo spleen cell blastogenesis, whereas the 80% and unprecipitated fractions had no inhibitory activity. Using Sephadex G-200 chromatography, the 2nd protein fraction (fraction II) contained an inhibitor of both DNA polymerases (IDP) and DNA synthesis (IDS) activity, which possessed no cytotoxic activity. In vitro DNA polymerase alpha activity was suppressed by fraction II, whereas DNA polymerase beta and gamma activities remained unchanged. Molecular weight of IDP/IDS, as determined by Sephadex G-200 gel filtration chromatography, was approximately 14,500. Attempts to separate IDP/IDS activities found in fraction II by anion-exchange chromatography and slab gel electrophoresis were not successful, which suggested that the 2 activities were the same or very similar molecules.
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PMID:Suppressor cell activity in tumor-bearing mice. III. Co-purification of a factor inhibiting cellular DNA synthesis and DNA polymerase activity. 645 73

A new procedure for inducing and purifying endo-beta-galactosidase from Escherichia freundii was described. The enzyme was found to be induced with high efficiency in culture medium containing Smith-degraded hog gastric mucin, which was prepared from a commercially available starting material. Endo-beta-galactosidase was then purified by ammonium sulfate fractionation, DEAE-Sephadex chromatography, and affinity chromatography on Sepharose conjugated with the Smith-degraded mucin. The enzyme thus purified by only three steps showed no other glycosidase or protease activities and had higher specific activity compared to the previous method. This new method has a great advantage since the gastric mucin is abundantly available and the efficiency of enzyme production was high without significant induction of exoglycosidase. The hydrolysis of oligosaccharides, glycosphingolipid, and keratansulfate was studied by using this newly purified enzyme. Kinetic data indicate that hydrolyzability of these substrates is largely affected by substrate concentration, enzyme concentration and the structure of substrates. Based on these results, the specificity of E. freundii endo-beta-galactosidase was discussed.
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PMID:Purification and characterization of endo-beta-galactosidase from Escherichia freundii induced by hog gastric mucin. 678 49


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