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:3.1.1.53 (sialidase)
2,694 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Observations have been made on two brothers who had progressive ataxia, intention myoclonus and visual failure starting early in the third decade of life. Their parents were consanguineous. The brothers showed bilateral cherry red spots at the maculae and bilateral perinuclear cataracts; their intelligence was preserved. Urine was found to contain large amounts of sialylated oligosaccharides; cultured skin fibroblasts showed deficiency of the enzyme sialidase (neuraminidase). Studies on leucocytes and cultured skin fibroblasts showed aberrant electrophoretic mobilities of six enzymes all of which are known to be glycoproteins, and this has been attributed to excessive amounts of sialic acid on the enzyme molecules. The clinical features together with the biochemical findings indicate that these are further cases of the newly described condition Sialidosis Type 1 and it is suggested that the electrophoretic findings might be typical of the condition.
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PMID:Sialidosis type 1: cherry red spot-myoclonus syndrome with sialidase deficiency and altered electrophoretic mobility of some enzymes known to be glycoproteins. II. Enzymes studies. 49 93

A family is described with three affected brothers, two of whom were examined, born to consanguineous parent, who in early adult life began to experience ataxia, intention myoclonus, and progressive visual failure. The brothers examined had cherry red spots at the maculae and cataracts. They were of normal intelligence. The intention myoclonus responded partially to treatment with clonazepam and pheneturide, but not to 5-hydroxytryptophan in combination with carbidopa or to sodium valproate. Studies in one patient showed the excretion of large quantities of sialylated oligosaccharides in the urine. Both patients showed deficient sialidase activity in their cultured fibroblasts. Further studies on cultured skin fibroblasts revealed increased electrophoretic mobility of six glycoprotein enzymes that was returned approximately to normal by treatment with sialidase. The clinical and biochemical findings indicate that these patients are further cases of the newly described condition sialidosis type 1.
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PMID:Sialidosis type 1: cherry red spot-myoclonus syndrome with sialidase deficiency and altered electrophoretic mobilities of some enzymes known to be glycoproteins. 1. Clinical findings. 51 62

Mucolipidosis I is characterized by Hurler-like features and skeletal dysplasia with a cherry-red macular spot and signs of neurodegeneration involving neuronal cells and myelin. Excessive amounts of sialic acid-containing compounds were found in cultured fibroblasts, leukocytes, and urine of a patient with a clinical phenotype of mucolipidosis I. In cultured fibroblasts, profoundly diminished activity of an alpha-N-acetylneuraminidase (sialidase) was found. Mucolipidosis I thus appears to be a distinct disorder of complex carbohydrate catabolism caused by the genetic deficiency of a neuraminidase.
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PMID:Mucolipidosis I--a sialidosis. 61 Apr 23

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.
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PMID:A comparative study of sialyloligosaccharides isolated from sialidosis and galactosialidosis urine. 177 19

Cultured human fibroblasts contain two sialidases that degrade gangliosides such as GM3: a lysosomal activity that appears identical with the activity towards water-soluble substrates and that is deficient in the genetic lysosomal disorder sialidosis, and another enzyme that seems localized on the external surface of the plasma membrane. In this report we show that both enzymes can be differentiated in the presence of each other by choice of the detergent used for activation, and also by the inhibitory action of some polyanionic compounds such as sulphated glycosaminoglycans. The lysosomal ganglioside GM3 sialidase is greatly stimulated by sodium glycodeoxycholate and, to lesser degrees, by sodium glycocholate and sodium cholate. The ganglioside GM3 sialidase of the plasma membrane is not measurably active under the conditions of the lysosomal enzyme but is specifically activated by the non-ionic detergent Triton X-100. The glycodeoxycholate-stimulated, but not the Triton-activated, ganglioside GM3 sialidase activity was profoundly diminished in cell lines from patients with the lysosomal disorders sialidosis and galactosialidosis; however, both activities were normal in fibroblasts from patients with mucolipidosis IV, previously thought to be a ganglioside sialidase deficiency disorder. Both the lysosomal and the plasma membrane ganglioside GM3 sialidases were inhibited by sialic acids, suramin, dextran sulphate and sulphated glycosaminoglycans. Among the latter, heparin and heparan sulphate showed a much higher inhibitory potency towards the plasma membrane ganglioside GM3 sialidase than towards the lysosomal onw.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Lysosomal and plasma membrane ganglioside GM3 sialidases of cultured human fibroblasts. Differentiation by detergents and inhibitors. 191 May 82

Electrophysiological investigation was performed in 3 patients with beta-galactosidase and sialidase deficiencies (sialidosis type 2) in order to elucidate the underlying mechanism of intention myoclonus. It is a rare neuronal storage disease that begins in childhood with mental retardation, skeletal abnormalities, progressive myoclonus and cherry-red spots in the macula. Electrophysiological studies showed paroxysmal activities in the EEG, consistent temporal relationship between the EEG spikes and myoclonic jerks demonstrated by jerk-locked averaging, high amplitude somatosensory evoked potentials with altered wave form, and enhanced long-loop reflexes. These results suggest that there is a hyperexcitability of the cerebral cortex, which results in induction of intention myoclonus. The intention myoclonus in sialidosis type 2 is consistent with 'cortical reflex' myoclonus described in progressive myoclonic epilepsy due to various etiologies.
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PMID:Electrophysiological studies of myoclonus in sialidosis type 2. 257 48

In this report we present evidence for the existence of a lysosomal ganglioside sialidase. The sialidase activity was solubilized by sonication and stimulated by cholate. The absence of ganglioside sialidase activity in sialidosis patients indicates that lysosomal sialidase is active towards gangliosides and glycoproteins. The plasma membranes were associated with two types of ganglioside sialidase activities, one was enhanced by cholate while the other was partially inhibited by this detergent.
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PMID:The identification of lysosomal ganglioside sialidase in human cells. 275 93

Sensitive assays for the determination of the ganglioside sialidase activity of fibroblast homogenates were established using ganglioside GM3, 3H-labelled in the sphingosine moiety, as a substrate. Ganglioside GM3 sialidase activity was greatly stimulated by the presence of the non-ionic detergent Triton X-100 and was further enhanced by salts such as NaCl; the optimal pH was 4.5. The subcellular localization of this activity was determined by fractionation using free-flow electrophoresis and found to be exclusively associated with the marker for the plasma membrane, but not with that for lysosomes. This Triton-stimulated ganglioside sialidase activity was selectively inhibited by preincubating intact cells in the presence of millimolar concentrations of Cu2+, suggesting that the activity resides on the external surface of the plasma membrane. In normal fibroblasts homogenates, ganglioside GM3 sialidase was also greatly stimulated by sodium cholate. In contrast to the Triton X-100-activated reaction, however, it was not diminished by prior incubation of intact cells in the presence of Cu2+. Only after cell lysis was Cu2+ inhibitory. the cholate-stimulated ganglioside sialidase activity thus paralleled the behaviour of the lysosomal 4-methylumbelliferyl-alpha-D-N-acetylneuraminic acid (4-MU-NeuAc) sialidase. In fibroblasts from sialidosis patients, the cholate-stimulated ganglioside GM3 sialidase activity, but not that of the Triton-activated enzyme, was profoundly diminished. In fibroblasts from patients with mucolipidosis IV (ML IV), both the Triton X-100- and the cholate-stimulated ganglioside GM3 sialidase activities were in the range of normal controls. The Triton-activated enzyme was associated with the plasma membrane in the same manner as in normal cells. Our findings suggest that, in human fibroblasts, there exist two sialidases that degrade ganglioside GM3: one on the external surface of the plasma membrane, and another that is localized in lysosomes and seems identical with the activity that acts on sialyloligosaccharides and 4-MU-NeuAc. As neither activity was found to be deficient in ML IV fibroblasts, our results argue against the hypothesis of a primary involvement of a ganglioside GM3 sialidase in the pathogenesis of ML IV.
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PMID:Ganglioside GM3 sialidase activity in fibroblasts of normal individuals and of patients with sialidosis and mucolipidosis IV. Subcellular distribution and and some properties. 277 95

Sialuria and sialidosis represent the two known types of genetic errors of sialic acid metabolism. Sialuria type I (or "massive Sialuria") remains a very rare disease, characterized by the daily excretion of 10 g of N-acetylneuraminic acid. Although the primary defect has not been established, the absence of a feedback inhibition of the anabolic reactions is probably involved in the massive production of free sialic acid. Sialuria type II (Salla disease) and type III are lysosomal storage diseases and the patients have shown to have a 10 to 15 fold increase in the amount of free sialic acid in urine. These sialurias probably involve a defect in translocation of sialic acid from lysosomes to the site of biosynthesis. The sialidase deficiency has been found to be responsible of a number of storage diseases previously unclassified or described as "lipomucopolysaccharidosis" or "mucolipidosis I". The sialidase deficiency, or Sialidosis, is characterized by and increased urinary excretion of sialyloligosaccharides and storage of sialylated compounds. A third type of genetic error, the combined beta-galactosidase-sialidase deficiency, is due to the genetic deficiency of a 32 KD "protective protein" which is part of the complex formed between multimeric beta-galactosidase and sialidase.
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PMID:[Genetic disorders of N-acetylneuraminic acid metabolism: sialurias and sialidoses]. 293 84

The inherited human disorders sialidosis and galactosialidosis are the result of deficiencies of glycoprotein-specific alpha-neuraminidase (acylneuraminyl hydrolase, EC 3.2.1.18; sialidase) activity. Two genes were determined to be necessary for expression of neuraminidase by using human-mouse somatic cell hybrids segregating human chromosomes. A panel of mouse RAG-human hybrid cells demonstrated a single-gene requirement for human neuraminidase and allowed assignment of this gene to the (pter----q23) region of chromosome 10. A second panel of mouse thymidine kinase (TK)-deficient LM/TK- -human hybrid cells demonstrated that human neuraminidase activity required both chromosomes 10 and 20 to be present. Analysis of human neuraminidase expression in interspecific hybrid cells or polykaryocytes formed from fusion of mouse RAG (hypoxanthine/guanine phosphoribosyltransferase deficient) or LM/TK- cell lines with human sialidosis or galactosialidosis fibroblasts indicated that the RAG cell line complemented the galactosialidosis defect, but the LM/TK- cell line did not. This eliminates the requirement for this gene in RAG-human hybrid cells and explains the different chromosome requirements of these two hybrid panels. Fusion of LM/TK- cell hybrids lacking chromosome 10 or 20 (phenotype 10+,20- and 10-,20+) and neuraminidase-deficient fibroblasts confirmed by complementation analysis that the sialidosis disorder results from a mutation on chromosome 10, presumably encoding the neuraminidase structural gene. Galactosialidosis is caused by a mutation in a second gene required for neuraminidase expression located on chromosome 20.
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PMID:Sialidosis and galactosialidosis: chromosomal assignment of two genes associated with neuraminidase-deficiency disorders. 308 2


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