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)

During a febrile upper respiratory tract illness this 4 year old boy developed left hemiparesis, which progressed to loss of walking and even of sitting finally to tetraplegia. The cerebrospinal fluid protein pattern showed blood-brain barrier damage with additional intrathecal IgG synthesis. The symptoms responded to steroid therapy but resumed and worsened on withdrawal. Only late, when visual evoked potentials and nerve conduction velocity proved to be impaired, was Krabbe disease diagnosed on the assay of cultured fibroblasts for galactocerebroside-beta-galactosidase. We discuss the significance of possible endogenous production of IgG in the CNS.
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PMID:Late onset globoid leukodystrophy: unusual clinical and CSF findings. 211 Jan 21

Sixteen pregnancies in families with children enzymatically diagnosed as having Krabbe disease (KD) were monitored for prenatal KD using the assay of galactosyl ceramide beta-galactosidase (GCG) in uncultured chorionic villi (CV), cultured CV, or cultured amniotic fluid cells (AFC). Prenatal KD diagnoses were made for 5 pregnancies on the basis of lower than 10% normal GCG activity in cultured CV or AFC. Uncultured CV were studied in 3 out of the 5 KD embryos, although the GCG activities of 14%-23% as compared with control villi were diagnostically inconclusive; the relatively high activities were considered to be caused by maternal GCG contamination of these very small villus samples. Although the villi from 6 of the other pregnancies yielded more conclusive results, the use of uncultured CV alone is not recommended for prenatal KD diagnosis, this material being subject to possible uncontrolled contamination with maternal enzyme.
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PMID:Prenatal enzymatic diagnosis of Krabbe disease (globoid-cell leukodystrophy) using chorionic villi. Pitfalls in the use of uncultured villi. 260 82

beta-Galactosylceramidase activity was deficient in leukocytes of a 5-month old child with neuro-degenerative disease. The activities of beta-galactosidase and arylsulphatase A were within normal limits. The beta-galactosylcerebrosidase activity in the mother's and father's leukocytes was 25% and 68%, respectively of the mean control values. A sharp decrease of beta-galactosylceramidase activity was found in cultured skin fibroblasts of the child. The data obtained indicate that the child suffered from globoid cell leukodystrophy (Krabbe's disease). The diagnosis was confirmed after liver and brain autopsy. The beta-galactosylceramidase was not revealed in these tissues. Typical globoid cells were observed in microscopical examination of the brain.
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PMID:[Biochemical diagnosis of globoid cell leukodystrophy (Krabbe's disease)]. 286 Jul 52

The metabolism of galactosylceramide was investigated in normal and twitcher mice, an animal model for human globoid cell leukodystrophy. The findings were compared with data obtained on human tissues. In vitro studies demonstrated that there were two genetically distinct enzymes that hydrolyze galactosylceramide: galactosylceramidase I and II. The former was deficient in the twitcher, while the latter was intact. beta-Galactosidase preparations purified from normal mouse liver possessed the activity to hydrolyze galactosylceramide when the assay conditions for galactosylceramidase II was used. Therefore, galactosylceramidase II was considered to be identical to GM1 ganglioside beta-galactosidase. In contrast to the human enzyme, the murine beta-galactosidase had a relatively high Km value toward galactosylceramide. The galactosylceramide-loading test demonstrated that the twitcher fibroblasts hydrolyzed the lipid at lower rates than seen in cases of human globoid cell leukodystrophy fibroblasts. These differences in galactosylceramidase II between murine and human tissues suggest that galactosylceramide accumulates in twitcher mice but not in humans with globoid cell leukodystrophy, even though galactosylceramidase I is genetically deficient in both human and this mouse model.
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PMID:Metabolism of galactosylceramide in the twitcher mouse, an animal model of human globoid cell leukodystrophy. 309 85

Enzymatic properties of beta-galactosidases with galactosylsphingosine (psychosine) and lactosylsphingosine as the substrates were examined. Although bile salts were stimulatory on the hydrolysis of the glycolipids in normal brain and cultured fibroblasts, the hydrolytic activities could be readily assayed, without detergents. The in vitro hydrolysis of lactosylsphingosine in cultured fibroblast homogenates was catalyzed by two enzymes, as is the case with the hydrolysis of galactosylceramide and lactosylceramide. Lactosylsphingosine beta-galactosidase activities assayed in the absence and the presence of taurocholate (probably lactosylceramidase I) were deficient in fibroblasts from patients with globoid cell leukodystrophy, while the activity assayed with sodium cholate (probably lactosylceramidase II) was deficient in GM1 gangliosidosis fibroblasts. In contrast, galactosylsphingosine beta-galactosidase was not activated by cholate and the enzyme activities assayed with the no-additive and taurocholate systems were deficient in brain and fibroblasts from patients with globoid cell leukodystrophy, thereby indicating that the hydrolysis of galactosylsphingosine is catalyzed by one enzyme, galactosylceramidase I. Exogenous lipids and an activator protein purified from normal spleen activated galactosylsphingosine beta-galactosidase but they were inhibitory to lactosylsphingosine beta-galactosidase. Because the Km values of lactosylsphingosine beta-galactosidase assayed with cholate were several magnitude higher than those obtained with the no-additive system and because lactosylsphingosine is readily hydrolyzed with the no-additive system in vitro, it is likely that the in vivo hydrolysis of the lipid is catalyzed by only one enzyme, lactosylceramidase I.
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PMID:Hydrolysis of galactosylsphingosine and lactosylsphingosine by beta-galactosidases in human brain and cultured fibroblasts. 311 43

A 13-month-old white girl was the product of a normal pregnancy and delivered by caesarean section for breech presentation. Regression of motor milestones started by 11 months, when delayed language development was also noted. She was normocephalic without major dysmorphic features or organomegaly. Fundus examination disclosed a subtle cherry red spot bilaterally. No startle response was elicited. By 17 months she was extremely irritable and unable to tolerate liquids; there was symmetrical spasticity and florid cherry red spots. She died at 18 months of age. A systematic search for conditions associated with a cherry red spot was unrevealing. The absence of galactosylceramide galactosidase activity was unexpected and was confirmed on three occasions in two laboratories. Lactosylceramide I content, an enzyme thought to be identical to galactosylceramide-beta-galactosidase, was significantly decreased. The presence of a cherry red spot in Krabbe's disease, indicative of neuronal storage, has not been previously recognized. The existence of this variant has implications for genetic and biochemical studies.
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PMID:Galactosylceramide-beta-galactosidase deficiency in association with cherry red spot. 336 11

Chorionic villi obtained during the first trimester from a pregnancy at risk for Krabbe's disease were shown to have reduced cerebroside-beta-galactosidase (E.C.3.2.1.46) activity using the artificial substrate trinitrophenylaminolauryl galactocerebroside (TNPAL-galactocerebroside). Assay of this enzyme in cultured amniotic fluid cells following amniocentesis, performed at the patient's request confirmed the diagnosis. Termination of pregnancy was performed and subsequent enzyme studies of the fetal tissues were consistent with the diagnosis of Krabbe's disease, thus confirming that chorionic villi can be used for first trimester diagnosis of this condition.
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PMID:Krabbe's disease: first trimester diagnosis confirmed on cultured amniotic fluid cells and fetal tissues. 361 58

Galactosyl ceramide beta-galactosidase activity was determined in chorionic villi (CV) samples obtained between the 9th and 11th weeks of gestation from 5 women with pregnancies at risk for Krabbe's disease (globoid-cell leukodystrophy, KD). These enzyme activities were compared with those in controls, as well as with those in cultured amniotic fluid cells (AFC) from one of the five at-risk pregnancies and from 29 KD-risk pregnancies studied previously. The results of these CV enzyme analyses were such that one case of fetal KD was clearly diagnosable, one fetal genotype heterozygous for KD was presumed, and three normal fetal genotypes were suggested. The use of both uncultured and cultered CV can be recommended for prenatal KD testing, but AFC may continue to play an important role, too. Of the 58 prenatal KD tests we have evaluated since 1974, a positive diagnosis of Krabbe's disease was made (and confirmed after termination of pregnancy when feasible) in 23 which is significantly more than 25% of 58.
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PMID:Prenatal enzymatic diagnosis and exclusion of Krabbe's disease (globoid-cell leukodystrophy) using chorionic villi in five risk pregnancies. 369 78

The synthesis of L-galactosylceramide is described. Data are presented indicating that this enantiomorph of D-galactocerebroside is not cleaved by galactocerebroside-beta-galactosidase obtained from mammalian tissues. The synthesis of L-glucosylceramide and beta-D-glucothiocerebroside are outlined. These compounds are also refractory to catabolism by glycosidases in mammalian tissues that catalyze the hydrolysis of naturally occurring cerebrosides. L-Hexosyl- and thioanalogs of cerebrosides and perhaps psychosines as well may be helpful for investigating the pathogenesis of Krabbe's disease and Gaucher's disease.
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PMID:Animal and cellular models of sphingolipid storage disorders of humans. 382 6

Enzyme replacement with liposomes containing beta-galactosidase obtained from charonia lumpas was carried out in murine globoid cell leukodystrophy (GLD). Charonia lumpas beta-galactosidase was able to hydrolyze galactocerebroside trapped into liposomes prepared from lecithin, cholesterol and sulfatide (molar ratio; 7:2:1). Liposomes containing charonia lumpas beta-galactosidase were successfully incorporated into the mouse tissues. 3H-galactocerebroside labeled liposomes were also incorporated into mouse liver, spleen and other tissues. The accumulation rate of 3H-galactocerebroside into twithcer mice liver and spleen was almost 40 to 100 times higher than those of controls and degraded to 70 to 80% of accumulated radioactivity of 3H-galactocerebroside by single injection of liposomes containing charonia lumpas beta-galactosidase. Results suggest that exogeneous enzyme trapped in liposomes can be useful for the correction of accumulated compound.
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PMID:Enzyme replacement with liposomes containing beta-galactosidase from Charonia lumpas in murine globoid cell leukodystrophy (twitcher). 391 36


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