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)

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 clan GH-A is a group of more than 200 proteins representing nine established families of glycosyl hydrolases that act on a large variety of substrates. This clan includes five enzymes implicated in lysosomal storage diseases: beta-glucuronidase (Sly disease), beta-glucocerebrosidase (Gaucher disease), beta-galactosidase (Landing disease and Morquito type B disease), beta-mannosidase (mannosidosis) and alpha-L-iduronidase (Hurler-Scheie disease). Examination of known 3D structures from some families of the clan allowed us to deduce structural and functional features shared by these proteins. We then used the hydrophobic cluster analysis method to study the protein sequences of the entire clan. Our results reveal that, despite low levels of sequence identity, all the proteins of the clan (including the aforementioned lysosomal enzymes) likely share a similar catalytic domain consisting of an (alpha/beta)8 barrel with conserved functional amino acids located at the C-terminal ends of six of the eight strands constituting the beta-barrel. Interestingly, several mutations reported to be responsible for lysosomal storage diseases are located within these conserved regions of the lysosomal enzyme catalytic domains.
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PMID:Active-site motifs of lysosomal acid hydrolases: invariant features of clan GH-A glycosyl hydrolases deduced from hydrophobic cluster analysis. 913 34

Extensive clinical heterogeneity is seen in lysosomal storage disorders, regarding the age of onset and severity of symptoms, the organs involved, and effects on the central nervous system. A broad phenotypic spectrum is seen, for example, in mucopolysaccharidosis type I (Hurler/Scheie disease), Gaucher disease, the several forms of GM2-gangliosidosis and the different manifestations of beta-galactosidase deficiency (GM1-gangliosidosis and Morquio disease type B). Variable clinical expression of the same enzyme defect is not well understood. The presence of different mutations is only part of the explanation, as intrafamilial variability is observed in many cases. Other mechanisms, for example the effect of specific activators, may also have an influence on phenotype.
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PMID:Variable clinical presentation in lysosomal storage disorders. 1175 78

In order to estimate the cumulative incidence rates of the mucopolysaccharidoses (MPS) in Germany, a retrospective epidemiological survey covering the period between 1980 and 1995 was implemented. Multiple ascertainment sources were used to identify affected patients. A prevalence of approximately 0.69 cases per 100,000 births was obtained for MPS I (Hurler phenotype). Within the study period, 4 patients with Hurler/Scheie phenotype and 7 cases with Scheie disease were detected. The cumulative incidence for MPS II (Hunter syndrome) was estimated as 0.64 cases per 100,000 births (1.3 cases per 100,000 male live births); that for MPS III (Sanfilippo syndrome types A, B and C) as 1.57 cases in 100,000 births; that for MPS IV A (Morquio syndrome) as 0.38 cases in 100,000; and that for MPS VI (Maroteaux-Lamy syndrome) as 0.23 cases per 100,000 births. Two cases of MPS IVB (beta-galactosidase deficiency) have been identified, but no patients with MPS VII or MPS IX. A relatively high number of patients with MPS IIIB, MPS IVA and MPS VI were of Turkish origin. The crude rate for all types of mucopolysaccharidoses is approximately 3.53 cases in 100,000 live births. The cumulative incidence pattern of MPS in Germany was compared with the corresponding rates among other industrial nations obtained from recent literature: the crude cumulative rates for all types of mucopolysaccharidoses (3.4-4.5 in 100,000 live births) were similar among all published populations; however, different frequencies of the various forms of MPS were observed.
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PMID:Cumulative incidence rates of the mucopolysaccharidoses in Germany. 1643 94