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)

In human pancreas, soybean agglutinin (SBA) conjugated to horseradish peroxidase reacted with the acinar cells secreting blood group A and/or H antigen, but not with those secreting only B antigen. For detailed histochemical characterization of SBA staining, the effects of treatment with unlabeled lectins and of digestion of certain enzymes on SBA staining were investigated in formalin-fixed, paraffin-embedded pancreatic tissue from individuals of different blood groups. Pre-incubation of sections with unlabeled Dolichos biflorus agglutinin to block A antigen eliminated subsequent SBA staining in the cells secreting A antigen, although failing to induce any effects in those secreting H antigen. In contrast, pre-incubation with unlabeled Ulex europaeus agglutinin-I (UEA-I) to block H antigen abolished SBA staining in cells secreting H antigen but not in those secreting A antigen. Treatment with galactose oxidase yielded the same results as those with unlabeled UEA-I, i.e., SBA reactivity was significantly diminished in cells secreting H antigen but not in those secreting A antigen. Digestion with beta-galactosidase resulted in a slight decrease of SBA staining in the cells secreting H antigen. Accompanying the decrease of SBA staining, reactivity with Griffonia simplicifolia agglutinin-II (GSA-II) appeared for the first time in the enzyme-susceptible, SBA-reactive cells secreting H antigen. Pre-treatment with galactose oxidase abolished this effect of beta-galactosidase. The GSA-II reactivity disclosed by treatment with galactosidase was completely eliminated by digestion with beta-N-acetylhexosaminidase, indicating that GSA-II staining after digestion with galactosidase is due to exposed penultimate beta-N-acetyl-D-glucosamine residues. These results demonstrate that at least two substances react with SBA in acinar cells of human pancreas, one being terminal beta-N-acetyl-D-galactosamine residues of A antigen, and the other being terminal beta-D-galactose-(1----3 or 1----4)-beta-N-acetyl-D-glucosamine dimers in the precursor of blood group H antigen. Such dimers may exist in close proximity to L-fucose residues of H antigen, since unlabeled UEA-I blocked SBA staining.
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PMID:Histochemical reactivity of soybean agglutinin with blood group antigens and their precursor substances in acinar cells of human pancreas. 295 34

The permanent human cell lines preserving defects of lysosomal enzymes, GM1-1019-SV and SA-1077-SV, were established from the respective fibroblasts from patients with GM1-gangliosidosis and Sandhoff disease by transfection with replication origin-minus simian virus 40 DNA. These cells grow rapidly without entering senescence during more than 120 population doublings. The activity of beta-galactosidase in GM1-1019-SV and of beta-N-acetylhexosaminidase in SA-1077-SV was respectively 40- and 180-fold lower than that of normal fibroblasts.
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PMID:In vitro establishment of human fibroblasts of lysosomal diseases, GM1-gangliosidosis and Sandhoff disease, by transformation with origin-minus SV40 DNA. 299 May 94

A highly sensitive microassay method and a microscale purification system were developed to isolate the residual acid beta-galactosidase in GM1-gangliosidosis fibroblasts. The sensitivity of the microassay system, composed of a 96-well microplate and a microplate fluorometer, was 100-fold higher than that of the conventional system and the response was linear in the pmole range. Acid beta-galactosidase was characterized as a thiol enzyme which was inactivated by a mercuric compound. This enzyme was completely adsorbed on an Hg-agarose column and was easily eluted from the column by 10 mM 2-mercaptoethanol. The microscale purification system using Con A-Sepharose, PAT-Sepharose, and Hg-agarose column chromatography achieved 565- and 7,970-fold purifications of acid beta-galactosidase with an overall yields of 44% and 45% from normal and GM1-gangliosidosis fibroblasts, respectively. The purified enzyme fractions did not contain any other lysosomal enzyme activities except for a small amount of beta-N-acetylhexosaminidase activity.
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PMID:Acid beta-galactosidase from human fibroblasts. A microscale purification method monitored by a highly sensitive enzyme assay. 308 62

Percoll density gradient centrifugation was used for isolating large quantities of bradyzoites of Sarcocystis suicanis, which were used for enzymatic analysis. Crude extracts of bradyzoites contained activities suggestive of several acid hydrolases. Levels of acid and alkaline phosphatase were higher than those of beta-N-acetylhexosaminidase and beta-galactosidase. Acid phosphatase was purified 156-fold with an overall recovery of 54% using DEAE-Sepharose 4B and Sephadex G-200 chromatography. The partially purified enzyme was not a glycoprotein and had a molecular weight of approximately 170,000. The enzyme was markedly inhibited by Cu++, Hg++, and iodoacetamide, suggesting the presence of a sulfhydryl group. Sodium tartrate caused strong inhibition of the enzyme. The acid phosphatase of S. suicanis appears to be a unique enzyme that cannot be classified under high or low molecular weight acid phosphatases of widely diverse origin.
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PMID:Studies on the enzymes of Sarcocystis suicanis: purification and characterization of an acid phosphatase. 311 63

A sialylhexasaccharide fraction (S-5) of human milk was obtained as described by A. Kobata and V. Ginsburg [(1972) Arch. Biochem. Biophys. 150, 273-281] and labeled by reduction with NaB[3H]4. When subjected to affinity chromatography on immobilized wheat germ agglutinin (WGA), a single component representing 60% of the S-5 fraction was retarded by the column. The asialo derivative of the WGA-retarded oligosaccharide had a higher affinity for the WGA column than the native sialyloligosaccharide. The neutral hexaose was identified as lacto-N-neohexaose by sequential exoglycosidase digestions in combination with gel filtration analyses of digestion products. Enzymatic removal of the nonsialylated branch of the intact sialyloligosaccharide by jack bean beta-galactosidase and beta-N-acetylhexosaminidase resulted in a single sialyl[3H]tetraose which was identified as sialyltetrasaccharide c (NeuAc alpha 2-6Gal beta 1-4GlcNAc beta 1-3Gal beta 1-4GlcO[3H]) by cochromatography with authentic standard and specific antibody binding. Independent evidence for the structure of the sialylhexasaccharide was obtained by 500-MHz1H NMR spectroscopy of the WGA-purified oligosaccharide before and after neuraminidase digestion. The structural data are consistent with the following, previously undescribed, sialylhexaose in human milk: (formula; see text).
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PMID:A novel sialylhexasaccharide from human milk: purification by affinity chromatography on immobilized wheat germ agglutinin. 319 33

A panel of 42 rodent x cat somatic cell hybrids has been used to assign seven structural genes for lysosomal enzymes to specific chromosomes in the domestic cat. The assignments include alpha-glucosidase (GANAB) to chromosome D1, alpha-galactosidase (GLA) to the X chromosome, beta-galactosidase 1 (GLB1) to chromosome B3, beta-glucuronidase (GUSB) to chromosome E3, alpha-mannosidase A (MANA) to chromosome B3, alpha-L-fucosidase (FUCA) to chromosome C1, and hexosaminidase A (HEXA) to chromosome B3. In all cases, the feline lysosomal enzyme genes were located in linkage groups which were syntenic with their homologous positions in the human gene map. These assignments expand the genetic map of the cat and reaffirm the extensive syntenic homology between the chromosome maps of man and cat.
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PMID:Chromosomal mapping of lysosomal enzyme structural genes in the domestic cat. 322 Apr 74

4-(N-Methylcoumarin-7-yl) glycamines were employed in studying asparagine-linked carbohydrate chains of acid desialylated fetuin. The procedure was optimised for the reductive amination of oligosaccharides with 7-amino-4-methylcoumarin in the presence of Na(CN)BH3 to lead to oligosaccharide glycamines (AMC-OS). AMC-OS were obtained from dextran oligosaccharides and from oligosaccharides released by hydrazinolysis of asparagine-linked sugar chains of asialofetuin. Reverse-phase HPLC and exclusion HPLC with fluorimetric quantitation of AMC-OS is described. TSK Gel 2000 SW column was calibrated using dextran AMC-OS to give linear relationship ln Ni = k(ti/tr)+b, where ti/tr is retention time of the AMC-OS relatively to the reference AMC-trisaccharide, and Ni is calibration unit value, characterizing molecular size of AMC-OS. Three AMC-OS, Gal3GlcNAc3Man3GlcNAc2-AMC (I) and (II), and Gal2GlcNAc3Man3GlcNAc2AMC (III), were obtained from asialofetuin in a molar ration of 1:1.8:0.1. Acid treatment of AMK-OS (II) in desialylation conditions also gave AMC-OS (III), thus suggesting a partial degalactosylation of the glycoprotein sugar chains during the desialylation. Consequent digestion of AMC-OS (II) and (III) with Jack bean beta-galactosidase and beta-N-acetylhexosaminidase led to the same AMC-OS, Man3GlcNAc2AMC. The final digestion product of AMC-OS (I) was GalGlcNAcMan3GlcNAc2AMC, suggesting a structural difference in one of the antennas of the minor sugar chain of asialofetuin. The monosaccharide quantitation and exoglycosidase sequencing were carried out at a 100 pmole level.
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PMID:[Fluorescent derivatives of carbohydrates in the analysis of the structure of glycoconjugates. N-(4-methylcoumarin-7-yl) glycamines in the study of asparagine-bound carbohydrate chains of glycoproteins]. 342 43

Castanospermine, an inhibitor of alpha-glucosidase activity, was injected into rats to determine its effects in vivo. Daily injections of alkaloid, at levels of 0.5 mg/g of body weight, or higher, for 3 days decreased hepatic alpha-glucosidase to 40% of control values, whereas alpha-glucosidase in brain was reduced to 25% of control values and that in spleen and kidney was reduced to about 40%. In liver, both the neutral (pH 6.5) and the acidic (pH 4.5) alpha-glucosidase activities were inhibited, but the former was more susceptible. On the other hand, beta-N-acetylhexosaminidase activity was elevated in the livers of treated animals, whereas beta-galactosidase activity was unchanged and alpha-mannosidase activity was somewhat inhibited. Livers of treated animals were examined by light and electron microscopy and compared to control animals to determine whether changes in morphology had occurred. In treated animals fed normal rat chow, the hepatocytes were smaller in size and simplified in structure, whereas the high-glucose diet lessened these alterations. Furthermore, in those animals receiving castanospermine at 1.0 mg or higher per g of body weight for 3 days, there was a marked decrease in the amount of glycogen in the cytoplasm, while a large number of lysosomes were observed that were full of dense, granular material. That this dense material was indeed glycogen was shown by the fact that it disappeared when blocks of fixed tissue were pretreated with alpha-amylase. Glycogen levels in liver, as measured either colorimetrically or enzymatically, were somewhat depressed at the higher levels of castanospermine.
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PMID:Castanospermine inhibits alpha-glucosidase activities and alters glycogen distribution in animals. 388 59

Methylation analysis of ceramide tetrasaccharide isolated from human erythrocytes gave acetates of 2,3,6-tri-O-methylgalactitol and 2,4,6-tri-O-methylgalactitol in a ratio of 1:1, and about 50% of the galactose was oxidized by periodate. Rat kidney ceramide tetrasaccharide gave, in contrast, a much larger proportion of the acetates of 2,4,6-tri-O-methylgalactitol (ratio 1:0.3), and less than 20% of the galactose was oxidized by periodate. Sequential degradation by beta-N-acetylhexosaminidase, alpha-galactosidase, and beta-galactosidase showed ceramide tetrasaccharides to have identical carbohydrate sequences and anomeric structures. The major part of ceramide trihexoside derived from rat kidney ceramide tetrasaccharide migrated on thin-layer chromatography more slowly than that derived from other ceramide tetrasaccharides. The structure of a major part of rat kidney ceramide tetrasaccharide was thus determined to be GalNAcbeta(1-->3)Galalpha(1-->3)Galbeta(1-->4)Glcbeta(1-->1)Cer, whereas other ceramide tetrasaccharides have Galalpha(1-->4) structure at the penultimate residue.
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PMID:Structures of ceramide tetrasaccharides from various sources: uniqueness of rat kidney ceramide tetrasaccharide. 434 27

Sphingolipidoses are an heterogeneous group of inherited disorders of lipid metabolism affecting primarily the central nervous system. These disorders occur chiefly in the pediatric population, and the degenerative nature of the disease processes is generally characterized by diffuse and progressive involvement of neurones (gray matter) with psychomotor retardation and myoclonus or of fiber tracts (white matter) with weakness and spasticity. Biochemical research has identified the defects in the sphingolipidoses to specific lysosomal enzymes. For example, Niemann-Pick disease lacks sphingomyelinase; Krabbe's disease lacks galactocerebrosidase; Gaucher's disease lacks beta-D-glucosidase; metachromatic leukodystrophy lacks sulfatase; Tay-Sachs disease lacks hexosaminidase A; and generalized gangliosidosis lacks beta-galactosidase. Although there are no currently available modes of rendering corrective therapy in these disorders, a definitive diagnosis is possible both antepartum as well as postpartum. This information provides a sound and accurate basis for genetic counseling.
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PMID:Sphingolipidoses. 555 2


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