Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.23 (beta-galactosidase)
 14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Human fetal tissues derived from prostaglandin-induced abortuses (9--18 wk fertilization age) have been utilized to evaluate sphingolipid composition and catabolism. Sphingolipid composition (lipid-hexose, sulfatide, and lipid-bound NANA) was assessed in fetal brain. Sphingolipid catabolism was evaluated in fetal lung and brain through the measurement of relevant acid hydrolases (arylsulfatase A, beta-galactosidase, and hexosaminidase). During the fetal period studied, the parameters of sphingolipid composition revealed variability but no consistent pattern of change. Each acid hydrolase was readily detected. Enzyme specific activities revealed no variation during the 9 fetal wk studied. Cellulose acetate electrophoresis yielded the anticipated isoenzyme patterns for each acid hydrolase with little variation during the period of study. The compositional values support current concepts of cerebral development during this period of fetal life. Together with the catabolic analyses, these studies provide normative data relative to the assessment of metabolic abnormalities during this period of fetal development.
 ...
PMID:Sphingolipid composition and catabolism in human fetal tissues. 3 Dec 73

Two cases of gangliosidosis due to aggregates of Gm1 are described. The first patient was a female infant with noticeable retardation in psychomotor development, coarse facies, hepatomegaly, and X-rays showing skeletal anomalies in the large bones, vertebral column, cranium and ribs. She died at the age of 10 months of a septic condition. The second patient was a male infant; deterioration in psychomotor development was first noticed 8 months after birth and this progressed slowly to arrive at a vegetative state with convulsions and myoclonus. The child died at the age of 4 years. There were no signs of enlargement of visceral organs but a cherry red stain was observed in the ophthalmologic examination. In the first case, necropsy revealed the presence of a deposit substance in the histiocytes of the hepatic sinusoids, spleen, pancreas, thymus, septi and pulmonary alveoli, intestinal lamina propria, epithelial cells of the renal glomeruli, and in the neurons and glial cells of the brain. The same deposits were observed only in the neurons and glial cells in the second case. Ultrastructural examination showed the presence of typical cytoplasmic membranous bodies in the central nervous system of both patients. The beta-galactosidase activity in the urine of both patients during life was zero. There was a higher than normal total amount of gangliosides in brain tissue samples from both (1906.7 and 2459.9 NANA/g respectively) as compared with normal values (724.0). This increase was proportional to the rise in Gm1 ganglioside (76.8 and 89.6 percent molar respectively) as compared to control (27.0). These clinical, morphologic, and biochemical data characterize both types 1 and 2 of gangliosidosis due to Gm1 aggregates.
 ...
PMID:[Gm1 gangliosidosis types 1 and 2 (author's transl)]. 10 76

Fragment 1, released from bovine plasma high-molecular-weight kininogen by the action of plasma kallikrein, is a glycopeptide with approximately 3 mol of each of N-acetylgalactosamine, galactose and sialic acid in one molecule. All these sugars were in the T-1 fragment obtained by tryptic digestion of fragment 1. Sialic acid can be completely released from the T-1 fragment by sialidase digestion. When this sialic acid-free T-1 fragment was incubated with purified diplococcal endo-alpha-N-acetylgalactosaminidase, all remaining sugars were released as a disaccharide. By Smith degradation and beta-galactosidase digestion, the structure of this disaccharide was found to be Gal beta 1 leads to 3GalNAc. Methylation analysis of the trisaccharide released from fragment T-1 by alkaline borohydride treatment indicated that all the galactose was obtained as the 2,4,6-tri-O-methyl derivative. Based on this evidence, the complete structure of the carbohydrate moieties of fragment 1 was proposed as Sialyl alpha 2 leads to 3Gal beta 1 leads to 3GalNAc. In addition, small amounts of a tetrasaccharide, Sialyl alpha 2 leads to 3Gal beta 1 leads to 3(Sialyl alpha 2 leads to 6)GalNAc also occurred as a carbohydrate chain of fragment 1.
 ...
PMID:The carbohydrate structure of a glycopeptide released by the action of plasma kallikrein on bovine plasma high-molecular-weight kininogen. 91 96

Sialic acid-containing carbohydrates were isolated from sialidosis urine by a combination of gel-filtration on Bio-Gel P-6 and medium-pressure anion-exchange chromatography on Mono Q. The Mono Q fractions were subjected to 500-MHz 1H-NMR spectroscopy, sugar analysis and analytical HPLC on Lichrosorb-NH2. These methods indicated the presence of various N-acetyllactosamine type sialyloligosaccharides differing from each other in branching pattern and sialic acid linkage types. Among the structures were fully and partially sialylated mono-, di-, tri- and tetra-antennary compounds. A comparison with the results from galactosialidosis urine indicated that essentially the same carbohydrates were present in both urines, but that the relative amounts of the various sialyloligosaccharides differ to some extent. Sialidosis urinary oligosaccharides contained relatively more alpha 2-6 linked sialic acid than oligosaccharides from galactosialidosis urine. It could be concluded that the additional beta-galactosidase deficiency in galactosialidosis did not influence the nature of the excreted material and that the sialidase deficiency determined completely the defective catabolism of glycoproteins in both sialidosis and galactosialidosis.
 ...
PMID:A comparative study of sialyloligosaccharides isolated from sialidosis and galactosialidosis urine. 177 19

The antigen designated as Chol-1 beta, detected by an antiserum specific for cholinergic neurons, has been purified to homogeneity from ganglioside mixtures extracted from Torpedo electric organ and pig brain. The final products from the two sources behaved identically in a wide range of tests and gave coincident immunopositive and Ehrlich-positive spots after thin layer chromatography in seven different solvent systems; they were thus considered to be identical and to constitute a single, pure chemical species. Gas-chromatographic analysis revealed the presence of long-chain bases, glucose, galactose, N-acetylgalactosamine, and sialic acid in integral molar ratios of 1:1:2:1:3; the compound's reactivity to cholera toxin after Vibrio cholerae sialidase treatment on thin layer chromatography and the recovery of GM1 as sole product of exhaustive sialidase treatment identified it as a member of the gangliotetrahexosyl series. From the products of partial enzymatic desialylation and treatment with beta-galactosidase and a comparison of the compound's immunoreactivity to anti-Chol-1 antisera with that of other trisialogangliosides of defined molecular structure, we were able to assign a disialosyl residue alpha-Neu5Ac-(2----8)-alpha-Neu5Ac-(2----3)- to the inner galactose, and we suggest GalNAc as a possible site of linkage of the third sialic acid.
 ...
PMID:Further studies on the gangliosidic nature of the cholinergic-specific antigen, Chol-1. 235 21

The subcellular distribution of sialyltransferase and its product of action, sialic acid, was investigated in the undifferentiated cells of the rat intestinal crypts and compared with the pattern observed in the differentiated cells present in the surface epithelium. Sialyltransferase was immunocytochemically detected with an antibody, affinity-purified on a beta-galactosidase/sialyltransferase fusion protein, which recognizes only protein epitopes of the enzyme. A similar pattern and intensity of immunolabeling were observed in the Golgi apparatus, apical and basolateral plasma membranes of both undifferentiated and differentiated absorptive cells. However, in the goblet cells, the mucus was only weakly labeled in cells present in the basal portion of the crypts but increased in intensity through the zone of migration to the surface epithelium. Sialic acid as detected with the Limax flavus lectin was observed in the Golgi apparatus and post-Golgi apparatus structures of both absorptive and goblet cells regardless of their position along the crypt-to-surface epithelium axis. However, a striking difference in the plasma membrane distribution of sialic acid existed between undifferentiated cells of the lower half of the crypts and those of the upper half and the surface epithelium: in the former, label was present in both the apical and basolateral domain, whereas in the latter it became restricted to the apical domain. These results suggest that the presence of sialyltransferase immunoreactivity in the goblet cell mucus and the polarization of sialic acid to the apical plasma membrane of both goblet and absorptive cells may be markers for the differentiated state.
 ...
PMID:Alteration in sialyltransferase and sialic acid expression accompanies cell differentiation in rat intestine. 245 28

In this study we further define cell surface carbohydrate structures relevant to cellular interactions that regulate erythropoiesis. An analysis of thymocyte cell surface negativity was made using fluoresceinated poly-L-ornithine (FITC poly-L-ornithine) as a probe that binds to negatively charged sites (i.e., sialic acid residues) at the cell surface. Two distinct subpopulations are labeled, comprising both intensely as well as weakly fluorescent subpopulations of thymocytes. Prior treatment of thymocytes with Vibrio cholerae neuraminidase (VCN), which removes cell surface sialic acid residues, markedly reduced the FITC poly-L-ornithine surface labeling of these cells. Distinct enzymatic modifications of regulatory cell functions were also assessed by the ability of thymocytes to function as separate regulatory subpopulations. Confirming our previous observations, treating thymocytes with VCN impaired the enhancement activity but had little effect on thymocyte regulatory ability to suppress erythroid colony growth. In contrast, treatment of thymocytes with galactose oxidase (GAO) or beta-galactosidase (beta-GAL) removed suppressor activity either before or after VCN treatment. A further exposure of GAO-treated thymocytes to sodium borohydride or hydroxylamine, which reduce D-galactose residues, restores their suppressor function and prevents enhancement. These differential enzymatic effects on thymocyte regulatory cell functions suggest that different carbohydrate structures may be involved in helper and suppressor activities for erythroid colony formation. Sialic acid residues may be associated with certain cells that function to enhance erythropoiesis, and D-galactose residues may be associated with the suppressor subpopulation.
 ...
PMID:Effects of neuraminidase on the regulation of erythropoiesis: III: Characterization of carbohydrate moieties on the surface of thymic regulatory cells that interact with erythroid colony-forming cells. 256 44

Sites of binding of eight different lectins (LTA, UEA I, WGA, SBA, DBA, CON A, PNA, RCA I) to cat submandibular gland were studied after exposure of tissue sections to sialidase, alpha-fucosidase, beta-galactosidase, alpha-mannosidase, beta-N-acetylglucosaminidase. All lectins were affected by enzymatic predigestion and the labeling of individual lectins was highly dependent upon the glycosidase used to pretreat the sections. Glycoconjugates of demilunar, acinar and ductal cells exhibited a different composition of terminal sequences. For example, fucose proved to form the disaccharide fucose-galactose in demilunar and acinar cells, whereas it was present with the sequence fucose-N-acetyl-D-glucosamine in striated duct cells. Sialic acid participated both to the terminal sequence sialic acid-galactose and sialic acid-N-acetyl-D-galactosamine either in demilunar or in ductal cells. Lectin labeling combined with glycosidase digestion was also helpful in verifying the influence of neighbouring oligosaccharides on the affinity of lectins for the respective sugars.
 ...
PMID:Enzymatic degradation and quantitative lectin labeling for characterizing glycoconjugates which act as lectin acceptors in cat submandibular gland. 271 45

Sialic acid-containing storage material was isolated from cultured human galactosialidosis fibroblasts, by a combination of gel filtration and anion-exchange chromatography on Mono Q. The obtained sialyloligosaccharides were analyzed by 500-MHz 1H-NMR spectroscopy in combination with sugar analysis and analytical HPLC. The storage material consisted of a series of completely sialylated N-acetyl-lactosamine type of structures having Man beta 1-4GlcNAc at the reducing terminus in common, similar to those recently reported for human sialidosis fibroblasts. Comparison of the storage material from both sources revealed only differences in their relative amounts. In control fibroblasts these compounds could not be detected. The nature of the accumulated compounds is in accordance with the alpha-neuraminidase deficiency in both genetic diseases. The additional deficiency of beta-galactosidase in case of galactosialidosis is not reflected in the storage material.
 ...
PMID:A comparative study of the accumulated sialic acid-containing oligosaccharides from cultured human galactosialidosis and sialidosis fibroblasts. 313 48

The carbohydrate-binding properties of wheat-germ agglutinin (WGA) have been studied by using glycopeptides isolated from the cell surfaces of a cultured murine myeloid cell line (416B). The glycopeptides were passed through affinity columns of lentil lectin (LCA), concanavalin A (Con A) and WGA arranged in series so that material reaching the WGA column had failed to bind to LCA or Con A. WGA-binding glycopeptides were step-eluted with 0.01 M, 0.1 M and 0.5 M-N-acetylglucosamine (GlcNAc), to yield weak (WGA-W), intermediate (WGA-I) and strong (WGA-S) affinity fractions. WGA-W and WGA-I contained 'N'- and 'O'-linked oligosaccharides bound to separate polypeptides. WGA-S consisted almost entirely of N-linked components. Our analytical work was concentrated mainly on the N-linked fractions. In these carbohydrates WGA affinity was directly proportional to molecular size but inversely related to N-acetylneuraminic acid content. The binding of the weak-affinity fraction was dependent on N-acetylneuraminic acid, but the intermediate- and strong-binding species interacted with the lectin by N-acetylneuraminic acid-independent mechanisms. N-linked glycopeptides in each WGA-binding class were almost totally degraded to monosaccharides by the concerted action of the exoglycosidases neuraminidase, beta-galactosidase and beta-N-acetylglucosaminidase. Treatment with endo-beta-galactosidase caused partial depolymerization, yielding some disaccharides but also a heterogeneous population of partially degraded components. These findings suggest that WGA binds with high affinity to internal GlcNAc residues in large oligosaccharides containing repeat sequences of Gal beta(1----4)GlcNAc beta(1----3) (i.e. polylactosamine-type glycans). N-Acetylneuraminic acid is involved only in low-affinity interactions with WGA. WGA therefore displays an intricate pattern of saccharide specificities that can be profitably utilized for structural analysis of complex carbohydrates.
 ...
PMID:Identification of two binding sites for wheat-germ agglutinin on polylactosamine-type oligosaccharides. 384 Jun 82


1 2 3 Next >>