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)

Clinical and neuropathological studies of a case of AB variant GM2-gangliosidosis have been presented. The patient was a 14 months old black female infant who had "black cherry spot" in the retinas. The total activities of beta-galactosidase and N-acetyl-beta-hexosaminidase, as well as the proportion of hexosaminidase A and B components in her serum and leukocytes were normal when the assays were carried out with artificial fluorogenic substrate. Diagnosis of GM2-gangliosidosis AB variant was established by an abnormal increase of GM2-ganglioside in the biopsied brain tissue, similar to classical Tay-Sachs disease. Her clinical manifestation appeared to be similar but somewhat milder than those of classical Tay-Sachs disease. Light microscopic features of the cerebral biopsy were also closely similar to Tay-Sachs disease and Sandhoff disease but gliosis and neuronal loss were less pronounced. Electron microscopic study revealed numerous membranous cytoplasmic bodies (MCB) and zebra bodies in neurons. In addition, varieties of large intracytoplasmic inclusions in astrocytes, a feature distinctly different from classical Tay-Sachs disease, were observed. Numerous cytoplasmic inclusions were also present in oligodendroglia, pericytes and microglial cells.
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PMID:GM2-gangliosidosis, AB variant: clinico-pathological study of a case. 17 79

Skin and conjunctival biopsy specimens from fourteen patients with neuronal storage diseases were investigated using an electron microscope. The diseases were Tay-Sachs disease, ceroid-lipofuscinosis (Jansky-Bielschowsky type), Niemann-Pick disease (type B), highly suspected adrenoleukodystrophy, I-cell disease, mucolipidosis of the beta-galactosidase deficient type, Hurler disease, Hunter disease and Morquio disease. This examination provided valuable diagnostic information on some neuronal storage diseases but not on Morquio disease or highly suspected adrenoleukodystrophy. False negative results may sometimes occur using this examination method. However, this examination suggests the usefulness of skin and conjunctival biopsy specimens as a diagnostic tool in some neuronal storage diseases.
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PMID:Electron microscopic examination of skin and conjunctival biopsy specimens in neuronal storage diseases. 23 94

The major beta-galactosidase of rabbit brain has been purified over 400-fold. The enzyme converts G-M-1-ganglioside; Gal beta-1 yields 3 GalNAc beta-1 yields 4 (NANalpha-2 yields 3) Gal beta-1 yields 4 Glc yields ceramide (G-M-1) into Tay Sachs ganglioside GalNAc beta-1 yields 4 (NANalpha-2 yields 3) Gal beta-1 yields 4 Glc yields ceramide (G-M-2-ganglioside) and ceramide lactoside, Gal beta-1 yields 4 Glc yields ceramide (Gal-Glc-Cer) into glucocerebroside, Glc yields ceramide (Glc-Cer). The enzyme also hydrolyzes the synthetic substrates NPh-Gal and MeUmb-Gal. It is eluted as a single peak from Sephadex G-200 columns when natural and synthetic substrates were used and has an isoelectric point of 6.3. We were unable to resolve activity towards G-M-1-ganglioside and Gal-Glc-Cer by polyacrylamide electrophoresis in two buffer systems. With G-M-1 the pH optimum was 4.3 in acetate buffer and the K-m value 78 mu-M while with Gal-Glc-Cer, a pH optimum of 4.5 and a K-m of 17 mu-M were found. Hydrolysis of both natural and synthetic substrates was inhibited by gamma-D-galactonolactone, D-galactose and lactose. The data strongly suggest that a single beta-galactosidase hydrolyzes all the substrates tested.
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PMID:Purification of G-M-1-ganglioside and ceramide lactoside beta-galactosidase from rabbit brain. 23 52

GM1-ganglioside hydrolysis by leukocytes and fibroblasts, tissues easily obtainable from patients, was investigated using 3H-labeled GM1 and was found to be at least as active as that reported for any other tissue. Sodium taurocholate was required for the reaction, the crude bile salt at an optimum concentration of 0.4% producing twice as much activity as pure taurocholate at its optimum concentration of 0.8%. Leukocyte GM1-ganglioside beta-galactosidase and 4-MU-beta-gal cleaving activities were similar, 134.5 +/- 23.3 and 179.8 +/- 25.4 nmol/h/mg protein, respectively. In cultured skin fibroblasts and amniotic fluid cells these enzyme activities were 4 to 5 times higher. Homozygotes for GM1-gangliosidosis showed negligible activity while in heterozygotes the leukocyte GM1-cleaving activity was reduced to one-third of control values. In leukocytes from patients with four other sphingolipid storage diseases the activity was either normal (Krabbe's, Tay-Sachs, Metachromatic leukodystrophy) or increased (adult Gaucher's).
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PMID:GM1-ganglioside beta-galactosidase in leukocytes and cultured fibroblasts. 41 12

A sister and brother, now aged 7 and 9 years, presented with developmental arrest, gait disturbance, dementia, and a progressive myoclonic epilepsy syndrome with hyperacusis in the second year of life. Then, spastic quadriparesis led to a decerebrate state. In the absence of macular or retinal degeneration, organomegaly, and somatic-facial features suggesting mucopolysaccharidosis, the presence of hyperacusis together with sea-blue histiocytes in bone marrow biopsies and deficient beta-galactosidase activity but normal glucosidase, hexosaminidase, and neuraminidase activity on lysosomal enzyme assays constitutes the clinical-pathologic-biochemical profile of GM1 gangliosidosis type 2. This is a rare, late infantile onset, progressive gray-matter disease in which beta-galactosidase deficiency is largely localized to the brain, though it can be demonstrated in leukocytes and cultured skin fibroblasts. It must be distinguished from the Jansky-Bielschowsky presentation of neuronal ceroid lipofuscinosis, mitochondrial encephalopathy, lactic acidosis, strokelike episodes (MELAS) and myoclonic epilepsy with ragged-red fibers (MERRF) syndromes, atypical presentations of GM2 gangliosidoses (Tay-Sachs and Sandhoff's diseases), primary sialidosis (neuraminidase deficiency), galactosialidosis, and Alpers' disease.
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PMID:GM1 gangliosidosis type 2 in two siblings. 158 15

Four aspects of advances in inborn errors of metabolism (IEM) are analysed: 1) concerning the general comprehension of the pathogenesis, genic localization and genetic heterogeneity; 2) clinical aspects, with description of new variants of known IEM or new IEM; 3) laboratory diagnostic tests presently used in our country: dosage of some genetic markers (arylsulfatases, hexosaminidases, beta-glycosidase; beta-galactosidase and sphingomyelinase), newborn populational screening (for hyperphenylalaninemia, and hypothyroidism), heterozygote detection (for Tay-Sachs disease) and also some prenatal diagnosis; 4) therapeutic aspects presenting substitutive treatment, special diets, plasmapheresis and leukapheresis. The first results of 4 cases of mucopolysaccharidosis treated with the last technic are presented.
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PMID:[Recent advances in inborn errors of metabolism]. 332 40

Brains of two patients with GM1 gangliosidosis type 1 and type 2, together with the age-matched control brains, were analyzed for glycosphingolipids. Six species of neutral glycolipids, eight species of gangliosides, and sulfatide were isolated from the diseased brains and identified. In addition to GM1 ganglioside and its asialo derivative, the diseased brains accumulated considerable amounts of gangliotriaosylceramide and glycolipids belonging to the globo series, the accumulation of which cannot be explained by deficient beta-galactosidase activity in this disease. GM4 ganglioside was detected in the type 2 brain, but not in type 1. As to fatty acid composition of monohexosylceramides and sulfatide in the two diseased brains, stearic acid was more predominant in the type 1 brain than in the type 2 brain. In light of our previous observations on a Tay-Sachs brain and present results, it appears that metabolism of the globo series glycolipids, which is active in normal brain at early infancy but inactive thereafter, remains in brains with GM1 gangliosidosis (types 1 and 2) and Tay-Sachs disease, reflecting a disturbance in development of the brain.
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PMID:Characterization of neutral and acidic glycosphingolipids in brains of two patients with GM1 gangliosidosis type 1 and type 2. 391 56

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

Assay conditions were studied for eight lysosomal enzymes in lymphoblastoid cell lines transformed by Epstein-Barr virus. The transformed lymphoblastoid cells retained all eight enzyme activities, though the levels sometimes differed from those in the peripheral lymphocytes or granulocytes. The levels of these eight lysosomal enzymes were measured in lymphoblastoid cells from 11 patients with hereditary lysosomal storage diseases--GMI-gangliosidosis, a variant of beta-galactosidase deficiency (sialidase deficiency with a partial beta-galactosidase deficiency), Tay-Sachs disease, Gaucher disease, Hurler syndrome, Scheie syndrome and I-cell disease--and from 20 of their obligate heterozygotes. No activity of enzymes that were deficient in the respective disease, except I-cell disease, was detected in the lymphoblastoid cells from the patient. In I-cell disease, the cells showed lower levels of some enzyme activities. beta-D-Galactosidase activity from heterozygotes of the patient with GMI-gangliosidosis and alpha-L-iduronidase activity from heterozygotes of the patient with Hurler syndrome were in carrier range. On sephadex G-150 gel filtration, beta-D-galactosidase in control material gave two peaks (I and II). In GMI-gangliosidosis, peak II was absent and peak I was markedly diminished. Peak II in the heterozygotes was smaller than that of control. On DEAE cellulose column chromatography of hexosaminidase, two major isoenzymes (hexosaminidase A and B) were detected in control. However, hexosaminidase A was not detected in Tay-Sachs disease, and the ratios of hexosaminidase (Hex) A/Hex B in the parents were lower than those in control.
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PMID:Lymphoblastoid cell lines, transformed by Epstein-Barr virus, in the enzymatic study of hereditary lysosomal storage diseases. 627 59

The generation of enzymes located in lysosomes, in cytosol or in endoplasmatic reticulum/Golgi complex is studied in heterokaryons in which chick erythrocyte nuclei are reactivated. The lysosomal enzymes, alpha-glucosidase (alpha-glu) and beta-galactosidase (beta-gal), are synthesized in heterokaryons obtained after fusion of chick erythrocytes with human fibroblasts of patients with Pompe's disease (alpha-glu-deficient) and GM1-gangliosidosis (beta-gal-deficient), respectively. The enzymes appear to be of chick origin and their activities can be detected at first around 4 days after fusion, i.e., at a time when the nucleoli in the erythrocyte nuclei have been reactivated. Maximal activities are reached around 15 days after fusion. No generation of the lysosomal enzyme beta-hexosaminidase is detected in the heterokaryons up to 23 days after fusion of chick erythrocyte with either beta-hexosaminidase A- and B-deficient fibroblasts (Sandhoff's disease) or beta-hexosaminidase A-deficient fibroblasts (Tay-Sachs disease). Similarly no expression of the cytosol enzyme glucose-6-phosphate dehydrogenase (G6PD) is fond up to 30 days after fusion, when chick erythrocytes are fused with fibroblasts from two different G6PD-deficient cell strains (residual activities of 4 and 20% respectively). Indirectly we examined N-acetyl-glucosamine-1-phosphate transferase activity, an enzyme located in the endoplasmic reticulum/Golgi region. This enzyme is needed for the phosphorylation of the lysosomal hydrolases and absence of its activity is the cause of the multiple lysosomal enzyme deficiencies in patients with I-cell disease. The retention of both, chick and human beta-galactosidase in the experiments in which I-cell fibroblasts were fused with chick erythrocytes indicates a reactivation of the gene coding for this phosphorylating enzyme. It also implies that this step in the processing of human lysosomal enzymes is not species-specific.
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PMID:Expression of lysosomal enzymes in human mutant fibroblast-chick erythrocyte heterokaryons. 629 65


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