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)

When rat peritoneal nonadherent cells were treated with inflammatory lipid metabolites and cultured with adherent cells in 1% fetal calf serum (FCS) supplemented medium RPMI 1640 (FCS medium) for 3 hr, markedly enhanced phagocytic and superoxide generating capacities of macrophages were observed. Stepwise preparation of conditioned medium of lysophosphatidylcholine (lyso-Pc)-treated B cells and untreated T cells in FCS medium generated a potent macrophage activating factor whereas cultivation of lyso-Pc-treated B cells alone in a 1% adult rat serum supplemented medium efficiently generated the macrophage activating factor. Generation of macrophage activating factor requires a precursor protein, serum vitamin D3-binding protein (DBP), as well as participation of lymphocyte glycosidases. The lyso-Pc-inducible beta-galactosidase of B lymphocytes and the Neu-1 sialidase of T lymphocytes modified bovine DBP (bDBP) to yield the macrophage activating factor, a protein with N-acetylgalactosamine as the remaining sugar. In contrast, lyso-Pc-inducible beta-galactosidase of B cells alone modified rat DBP (rDBP) to yield the macrophage activating factor, a protein with N-acetylgalactosamine as the remaining sugar. Thus, we conclude that bDBP carries a trisaccharide composed of N-acetylgalactosamine, galactose, and sialic acid while rDBP carries a disaccharide composed of N-acetylgalactosamine and galactose.
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PMID:Vitamin D3-binding protein as a precursor for macrophage activating factor in the inflammation-primed macrophage activation cascade in rats. 866 Aug 14

Serum vitamin D3-binding protein (Gc protein) can be converted by beta-galactosidase of B cells and sialidase of T cells to a potent macrophage activating factor, a protein with N-acetylgalactosamine as the remaining sugar moiety. Thus, Gc protein is the precursor of the macrophage activating factor (MAF). Treatment of Gc protein with immobilized beta-galactosidase and sialidase generates an extremely high titered MAF, Gc-MAF. When peripheral blood monocytes/macrophages of 52 patients bearing various types of cancer were incubated with 100 pg/ml of GcMAF, the monocytes/macrophages of all patients were efficiently activated. However, the MAF precursor activity of patient plasma Gc protein was found to be severely reduced in about 25% of this patient population. About 45% of the patients had moderately reduced MAF precursor activities. Loss of the precursor activity was found to be due to deglycosylation of plasma Gc protein by alpha-N-acetylgalactosaminidase detected in the patient's bloodstream. The source of the enzyme appeared to be cancerous cells. Radiation therapy decreased plasma alpha-N-acetylgalactosaminidase activity with concomitant increase of precursor activity. This implies that radiation therapy decreases the number of cancerous cells capable of secreting alpha-N-acetylgalactosaminidase. Both alpha-N-acetylgalactosaminidase activity and MAF precursor activity of Gc protein in patient bloodstream can serve as diagnostic and prognostic indices.
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PMID:Deglycosylation of serum vitamin D3-binding protein leads to immunosuppression in cancer patients. 866 21

Adrenergic responses of rat hepatocytes were studied by measuring Ins(1,4,5)P3(for the response via alpha 1-subtype receptors) and cAMP (for beta-subtype response) generation during brief incubation of cells with respective agonists. Hepatocytes from young rats with an age of 1 week displayed a very high beta response without a significant alpha 1 response. The beta response decreased and the alpha 1 response increased progressively as the age increased; the response was almost exclusively via alpha 1 receptors in hepatocytes of adult rats 9 weeks or more old. The beta response developed, again at the expense of the alpha 1 response, in hepatocytes from adult rats during the primary culture at low cell densities [(1-2.5) x 10(4) cells/cm2]. Such "alpha 1 to beta subtype switching' of adrenergic responses in vitro was totally inhibited by adding plasma membranes prepared from adult rat liver into the low-cell-density culture, but not inhibited at all by membranes from young rat liver. The inhibitory effect of adult rat liver membranes was lost when the membranes had been exposed to endoglycosidase F or beta-galactosidase but was not affected by prior treatment with sialidase. On the contrary, young rat liver membranes became inhibitory to "alpha 1 to beta subtype switching' after prior treatment with sialidase. Thus glycoproteins with unsialylated galactosyl termini on the surface of adult rat hepatocytes are likely to function as a determinant of the relative development of alpha 1/beta subtypes of adrenergic responses; the beta response is predominant in hepatocytes in the juvenile, presumably as a result of sialylation of the galactosyl termini of the functional glycoproteins.
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PMID:A role of asialoglycoproteins for plasma-membrane-induced inhibition of the switching from alpha 1 to beta subtypes in adrenergic response during primary culture of rat hepatocytes. 867 Jan 47

Generation of macrophage-activating factor requires a precursor protein, Gc protein (serum vitamin D3-binding protein), as well as participation of beta-galactosidase of inflammation-primed B lymphocytes and sialidase of T lymphocytes. The treatment of human peripheral blood mononuclear cells with an inflammatory lysophospholipid induced beta-galactosidase and sialidase activity of lymphocytes, leading to the generation of macrophage-activating factor and activation of monocytes/macrophages. However, lysophospholipid treatment of peripheral blood mononuclear cells from three infantile patients with osteopetrosis resulted in no significant activation of monocytes/macrophages. The lysophospholipid-inducible beta-galactosidase activity of B lymphocytes as well as that of the sialidase of T lymphocytes was found to be defective in these patients.
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PMID:Defective lymphocyte glycosidases in the macrophage activation cascade of juvenile osteopetrosis. 1038 96

When mouse peritoneal nonadherent (lymphocytes) cells were treated with lysophosphatidylcholine (lyso-Pc) and cultured with adherent cells (macrophages) in 1% fetal calf serum (FCS)- or adult mouse serum (AMS)-supplemented medium for 3 h, markedly enhanced phagocytic and superoxide-generating capacities of macrophages were observed. Stepwise cultivation of lyso-Pc-treated B cells and untreated T cells with an FCS-supplemented medium generated a macrophage-activating factor (MAF), whereas cultivation of lyso-Pc-treated B cells alone in AMS-supplemented medium was sufficient to generate the MAF. The accumulated evidence suggests that lyso-Pc-inducible beta-galactosidase of B lymphocytes and the Neu-1 sialidase of T lymphocytes modified the bovine serum vitamin D3-binding protein (DBP) to yield the MAF, a protein with N-acetylgalactosamine as the remaining sugar. In contrast, the lyso-Pc-inducible beta-galactosidase of B cells alone modified mouse DBP to yield the MAF. These observations led us to conclude that bovine DBP carries a trisaccharide composed of N-acetylgalactosamine, galactose, and sialic acid, whereas mouse DBP carries a disaccharide composed of N-acetylgalactosamine and galactose. Thus, macrophages of a T-cell-deficient nude (BALB/c nu/nu) mouse and a T-cell Neu-1 sialidase-deficient SM/J mouse were efficiently activated by administration of lyso-Pc.
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PMID:Role of vitamin D3-binding protein in activation of mouse macrophages. 875 64

The developmental profiles of sialidase, beta-galactosidase, beta-hexosaminidase and beta-glucosidase were compared to those of the gangliosides in rat brain and spinal cord. The glycosidase activities (enzyme units/g wet tissue), except beta-galactosidases, were found to be higher in brain than spinal cord, in adult rats. Among the hydrolases, beta-hexosaminidase showed a higher level of activity in both brain and spinal cord. In brain, the hydrolases, except beta-glucosidase, followed a similar developmental pattern, showing an increase from birth to 21 days, and then decreased to adult values by day 90. In the spinal cord, sialidase, beta-galactosidase, pH 3.1, and beta-hexosaminidase activities increased from birth to 21 days, reaching peak values. These activities then declined to adult values by 90 days of age. However, beta-galactosidase, pH 4.5, and beta-glucosidase activities showed a peak at day 14. Brain total ganglioside concentration (microgram N-acetylneuraminic acid/g tissue) increased slowly between birth and 7 days of age, followed by a rapid phase of increase to attain a peak value by day 21. The concentration of total gangliosides in the spinal cord is less when compared to the brain. The proportions of individual gangliosides in the central nervous system also vaired during development. The rapid phase of increase in enzyme activities between 0-7 and 14-21 days and a decrease thereafter is consistent with the turnover rate of gangliosides, which in rat brain is reported to be highest between 10 and 20 days.
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PMID:Postnatal development of glycosidases and gangliosides in the rat central nervous system. 888 81

Serum alpha-fetoprotein (AFP) is a glycoprotein of which the sugar chain is considered to show structural changes with malignancies. Microheterogeneity of the serum AFP carbohydrate structure was studied in samples from 35 patients with benign and malignant diseases. Sera were digested directly, extensively, and sequentially with sialidase. beta-galactosidase and beta-N-acetylhexosaminidase. Before and after digestion, sera were examined by means of lectin affinity electrophoresis using eight lectins. Relationships between AFP carbohydrate structures and liver diseases were elucidated by the lectin-reactive profiles and the effect of glycosidase digestion. More than 94% of the AFP carbohydrate structures found in patients with benign and malignant liver diseases were biantennary complex-type oligosaccharides. Changes in the AFP carbohydrate structures at the early stage of hepatocellular carcinoma revealed the addition of alpha 1-->6 fucose to the reducing terminal N-acetylglucosamine and monosialylated AFPs. In both advanced hepatocellular carcinoma and AFP producing extrahepatic malignancies, AFP carbohydrate structures were characterized as the further addition of beta 1-->4 N-acetylglucosamine and heterogeneity in the galactose and N-acetylglucosamine residues. Sequential glycosidase digestion and lectin affinity electrophoresis is useful for analysing the carbohydrate structures of serum glycoprotein.
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PMID:Comparison of carbohydrate structures of serum alpha-fetoprotein by sequential glycosidase digestion and lectin affinity electrophoresis. 889 7

Although the neuronal ceroid-lipofuscinoses (NCLs) are often referred to as lysosomal storage disorders, information on brain lysosomal hydrolases in NCLs is not available. We have determined the specific activities of several acid hydrolases in postmortem brain gray matter of infantile (INCL), late infantile (LINCL), juvenile (JNCL), and adult (ANCL) forms of NCL, patients affected with other neurological disorders (ON), and normal controls. The specific activities of beta-hexosaminidase A and B were significantly high in JNCL gray matter, whereas in LINCL, the increase is significant only in beta-hexosaminidase compared to the controls. A significant increase in the activities of alpha-mannosidase, beta-glucuronidase, and acid phosphatase was also observed in LINCL and JNCL patients compared to the control values. beta-galactosidase activity was also found to be elevated in JNCL brains over the controls. In contrast, activities of beta-glucosidase and sialidase appeared to be lowered in INCL and LINCL. On the other hand, alpha-fucosidase, beta-mannosidase, and sulfatase were unaffected in NCLs brains. Thus, the present data indicate NCLs related abnormalities in some of the acid hydrolases in brain gray matter, which are primarily glycoproteins of lysosomal origin. These data in conjuction with the reported association of sphingolipid activator proteins (SAP) A and D and lysosomal glycoproteins with NCL storage bodies imply abberations in the glycoconjugate metabolism and lysosomal function.
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PMID:Brain lysosomal hydrolases in neuronal ceroid-lipofuscinoses. 897 94

Transglycolytic synthesis of 3'-sialyl-N-acetyllactosamine by sequential use of beta-galactosidase from Bacillus circulans and trans-sialidase from Trypanosoma cruzi was described. These reactions depicted the first complete synthesis of a biologically important oligosaccharide with high regioselectivity avoiding use of glycosyltransferases and NDP sugars.
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PMID:Complete synthesis of 3'-sialyl-N-acetyllactosamine by regioselective transglycosylation. 898 45

Simplified HPLC protocols to determine the activity and linkage specificity and to detect the most commonly-encountered contaminants in available exoglycosidase preparations (Jacob and Scudder, Methods Enzymol., 230, 280-300, 1994) were developed. Monosaccharides and oligosaccharides were analyzed in a single chromatographic step using high-pH anion-exchange chromatography with pulsed amperometric detection. All analyses were performed with underivatized oligosaccharide substrates and by direct injection of unprocessed, diluted enzyme digests into the chromatograph. The sialidase from Newcastle disease virus was found to release both alpha (2-->3)- and alpha (2-->6)-linked Neu5Ac from a triantennary, lactosamine-type oligosaccharide. The activity of alpha-galactosidase from green coffee beans was assayed using Gal alpha(1-->3)[Fuc-alpha(1ar2)]Gal by detection of Gal and Fuc alpha(1-->3)Gal. The linkage specificities of beta-galactosidases from Streptococcus pneumoniae and bovine testis were assessed using Gal beta(1-->3 or 4)GlcNAc beta(1-->3)beta(1-->4)Glc as substrates. Contaminating beta-N-acetylhexosaminidase activity in the beta-galactosidase preparation was assayed using an agalactobiantennary oligosaccharide. The alpha(1-->3 or 4) linkage specificity of fucosidase III from almond meal was confirmed (Scudder et al., J. Biol. Chem. 265, 16472-16477, 1990) by its inactivity against a biantennary oligosaccharide with all Fuc residues linked alpha(1-->6). An alpha-fucosidase from chicken liver was found to cleave alpha(1-->2,3 or 6)-linked Fuc residues from oligosaccharides. The activity of jack bean (Canavalia ensiformis) alpha-mannosidase was assayed with a relatively resistant substrate, Man alpha(1-->3)- Man beta(1-->4)GlcNAc. A GlcNAc beta(1-->4)-terminated triantennary oligosaccharide was used to assay for contaminating beta-N-acetylhexosaminidase activity in alpha-mannosidase preparations and to determine the linkage and branch specificity of beta-N-acetylhexosaminidase at different enzyme concentrations.
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PMID:Exoglycosidase purity and linkage specificity: assessment using oligosaccharide substrates and high-pH anion-exchange chromatography with pulsed amperometric detection. 887 65


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