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)

Six glycoside hydrolases in the culture medium of Bacteroides fragilis--alpha-glucosidase, beta-glucosidase, alpha-galactosidase, beta-galactosidase, beta-N-acetylglucosaminidase, and alpha-L-fucosidase-were systematically purified by ammonium sulfate precipitation, gel filtration chromatography, and density gradient isoelectric focusing. The isoelectric focusing resolved the glycosidases into distinct, well-separated fractions and revealed three differently charged forms of beta-N-acetylglucosaminidase and of alpha-L-fucosidase. Furthermore, alpha-glucosidase and beta-N-acetylglucosaminidase were shown to possess dual affinities for the respective galactoside substrates, and beta-galactosidase also hydrolyzed beta-D-fucoside. alpha-Glucosidase was purified to homogeneity, as indicated by a thin-layer isoelectric focusing zymogram technique. The glycosidases, with exception of beta-glucosidase and the acid alpha-L-fucosidase, were each separated from other glycosidic activities to 99%. The molecular weights varied between 58,000 and 125,000. The pH optima ranged from 4.8 to 6.9.
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PMID:Purification of glycoside hydrolases from Bacteroides fragilis. 625 Apr 77

The developmental patterns of four lysosomal enzymes have been investigated in liver, kidney, lung, heart, spleen, muscle and brain tissues of human fetuses at varius gestational ages. The largest increment in the activity of all four enzymes, namely acid alpha-glucosidase, alpha-galactosidase, beta-galactosidase and acid phosphatase had been observed in kidney with a 6- to 12-fold increase between the second and third trimester of gestation. The activity of all liver and spleen enzymes also increased considerably during these periods. In muscle, however, only alpha-glucosidase and acid phosphatase showed an increase in the activity, and in lung, acid phosphatase and beta-galactosidase. Most of brain and heart enzymes, except acid phosphatase, did not change significantly during the observation period. The activities of these lysosomal enzymes were also measured in tissues of a normal adult individual, and aspects of the neonatal and postnatal development of these enzymes were discussed.
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PMID:Lysosomal enzyme activities of human fetal organs during development. 625 27

The enzyme activities of alpha-fucosidase (pH 4.0 and pH 5.5), alpha-galactosidase, beta-galactosidase, alpha-glucosidase (pH 4.5 and pH 6.0), beta-glucosidase, beta-glucuronidase, beta-hexosaminidase, and alpha-mannosidase (pH 4.5 and pH 5.5) were investigated in sera from cystic fibrosis (CF) patients. Several of these activities were significantly increased in sera from patients compared to age-matched control children. CF-patients in a more advanced stage of the disease had a tendency to higher values of some of these hydrolases than those in better condition. No new isoenzymes of these hydrolases were found. Only minor differences could be detected in the pH-profiles of alpha-mannosidase and acid phosphatase from age-matched normal controls, heterozygotes and homozygotes for CF. With our technique, alpha-mannosidase and acid phosphatase showed the same thermostability in CF-patients. CF-heterozygotes and age-matched controls, except at 56 degrees C, when the activity of acid-phosphatase in the plasma from adult CF-heterozygotes decreased more than that from adult controls
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PMID:Acid hydrolases in sera and plasma from patients with cystic fibrosis. 626 20

The present investigations on rat lung show that metabolic changes occurring around the 20th gestational day are accompanied by multiple alterations in the quantitative pattern of enzymes. This involves increases in two lysosomal enzymes (N-acetyl beta-glucosaminidase and beta-galactosidase) and a rise and fall in pyruvate kinase and alpha-glucosidase. The striking transient upsurge of adenylate kinase, however, is postponed until after birth. The normal diminution of thymidine kinase and peptidylproline hydroxylase is drastically enhanced by an injection of cortisol to fetal rats. Studies on human pulmonary tissues consisted in determining enzyme concentration from the ninth to the 21st week of gestation and an histologically normal adult lungs. The results show that the 15th to the 21st week of gestation is the period of increase in pyruvate kinase, adenylate kinase and alpha-glucosidase. The rise during the development of several enzymes (e.g., 5'-nucleotidase, alkaline phosphatase, and gamma-glutamyl transpeptidase) and the decline in thymidine kinase and peptidylproline hydroxylase, however, dose not begin until after the 21st week of gestation.
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PMID:Phosphotransferases and lysosomal enzymes in fetal human and rat lung. 626 41

The aim of our presentation was to show how we characterize cells cultured in monolayer system. Cytological and biochemical methods were used. Ovarian Krukenberg tumour fibroblasts were investigated and findings were correlated with normal human diploids (HDZ1) and with fibroblasts obtained from Blighted ovum. Cytomorphologically Malignancy associated changes in the tumour fibroblasts were found. Cytochemically acid phosphatase and alpha-naphtyl-esterase were positive (+++). PAS reaction was doubled in 18th passage. Cytogenetically normal human diploids were found. Biochemically enzymatic assay showed phosphopentose shunt is decreased in tumour fibroblasts and alpha-glucosidase and beta-galactosidase activities were significantly lower in these cells. A form of N-acetyl-beta-glucosaminidase fell during the investigation from normal 75% to lower percent (42% of the total activity). Much more parameters were obtained by different methods and Krukenberg tumour fibroblasts may be better understood. In vitro investigation makes a contribution to biomedical knowledge in cancer research.
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PMID:Cytological and biochemical methods for the characterization of in vitro cultured cells. 626 64

Preparations of isolated brush border plasma membrane of Hymenolepis diminuta and H. microstoma possess the following enzymatic activities: alkaline phosphohydrolase (E.C. 3.1.3.1); Type I phosphodiesterase (E.E. 3.1.4.1); ribonuclease (E.C. 3.1.4.22); adenosine triphosphatase (E.C. 3.6.1.3); and 5'-nucleotidase (E.C. 3.1.3.5). The following enzymatic activities could not be demonstrated in either membrane preparation: Type II phosphodiesterase (E.C. 3.1.4.18); cyclic adenosine-3', 5'-monophosphate phosphodiesterase (E.C. 3.1.4.17); leucine aminopeptidase (E.C. 3.4.11.1); maltase (alpha-glucosidase; E.C. 3.2.1.20); and lactase (beta-galactosidase; E.C. 3.2.1.23). These data generally agree with those of previous studies in which similar membrane-bound enzymes were demonstrated in intact (living) worms.
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PMID:A comparison of membrane-bound enzymes of the isolated brush border plasma membranes of the cestodes of Hymenolepis diminuta and H. microstoma. 628 Jan 22

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

The catalytic activities of N-acetyl-beta-D-glucosaminidase, beta-galactosidase and alpha-glucosidase in kidney and urine of diabetic rats were investigated in relation to the duration of diabetes, to the degree of constant hyperglycaemia and to the therapeutic control in the early stage of disease. The results suggest that the degree of constant hyperglycaemia and the duration of untreated diabetes are significant determining factors for the course of morphological changes. These changes are manifested as a decrease of the glycosidases in kidney (0.5 to 0.6 time the age-matched controls) and as moderate to severe enzymurias. Daily variation of blood glucose with inadequate insulin Lente therapy caused decreased N-acetyl-beta-D-glucosaminidase and beta-galactosidase activities in kidney as well as enzymuria. Since such changes can be correlated with histologically visible changes in the kidney, the measurement of these enzymes in urine is a simple way of monitoring the development of kidney damage in poorly controlled diabetes. When constant normoglycaemia was maintained for three weeks with insulin Ultralente in diabetic rats with a confirmed decrease of kidney glycosidases, the persisting morphological alteration of the organ was reflected by a urinary output of N-acetyl-beta-D-glucosaminidase.
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PMID:Effect of the degree of hyperglycaemia on the catalytic activities of glycosidases in kidney and urine of diabetic rats. 636 9

This study determined in a blind fashion the activity levels and thermostability properties of two lysosomal hydrolytic enzymes, acid phosphatase and alpha-mannosidase, in plasma samples from 25 cystic fibrosis (CF) patients and 25 age- and sex-matched normal controls. Mean alpha-mannosidase activity (3.2 +/- 1.0 mU/ml) and acid phosphatase activities (6.5 +/- 2.9 mU/ml) in CF patients were not significantly different from those found in normal individuals (2.8 +/- 0.7 and 7.6 +/- 3.4 mU/ml, respectively). Using stringent conditions no differences in thermostability properties of these enzymes were found between plasma from CF patients as compared to that of normal controls. When activity levels of these enzymes and of four additional hydrolytic enzymes, alpha-L-fucosidase, alpha-galactosidase, alpha-glucosidase and beta-galactosidase, were determined in submandibular saliva, no significant differences in enzyme levels between CF and age- and sex-matched controls were noted nor were thermostability differences found. Our data do not support the concept that altered properties of these enzymes are useful as markers for detection of CF homozygotes and heterozygotes, nor the hypothesis that the defect underlying this disease is a deficiency of post-translational modification of glycoproteins leading to their mis-compartmentalization and qualitative alteration.
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PMID:Plasma and submandibular saliva lysosomal enzymes in cystic fibrosis. 639 40

Castanospermine (1,6,7,8-tetrahydroxyoctahydroindolizine) was tested against a variety of commercially available glycosidases and found to be a potent inhibitor of almond emulsin beta-glucosidase, and also to inhibit fungal beta-xylosidase. This alkaloid was inactive on yeast alpha-glucosidase, alpha- or beta-galactosidase, alpha-mannosidase, beta-N-acetylhexosaminidase, beta-glucuronidase, alpha-L-fucosidase. Fifty-percent inhibition of beta-glucosidase required about 10 micrograms/ml of castanospermine. The amount of inhibition was uniform throughout the time course, and the inhibition with regard to substrate concentration (p-nitrophenyl-beta-D-glucopyranoside) appeared to be of the mixed type. Castanospermine was also a potent inhibitor of beta-glucocerebrosidase when assayed with fibroblast extracts using either a fluorimetric or a radioactive assay. Interestingly enough, castanospermine also inhibited the lysosomal alpha-glucosidase, and this inhibition required comparable levels of alkaloid to that required for inhibition of beta-glucocerebrosidase. However, a number of other lysosomal glycosidases were not sensitive to castanospermine (i.e., alpha- or beta-galactosidase, alpha- or beta-mannosidase, alpha- or beta-L-fucosidase, beta-N-acetylhexosaminidase, beta-glucuronidase).
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PMID:Castanospermine, a tetrahydroxylated alkaloid that inhibits beta-glucosidase and beta-glucocerebrosidase. 640 22


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