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)

beta-Galactosidase activity was investigated in one case of juvenile GM1-gangliosidosis. This patient exhibited normal activity of the neutral form of beta-galactosidase (measured as beta-glucosidase activity) and normal pH curve of residual acid beta-galactosidase activity in leucocytes and fibroblasts. A shift towards more neutral pH optimum was seen in the beta-galactosidase enzyme occurring in serum. The communication also presents a study of the relationship of the different beta-galactosidases in human liver using isolated urine oligosaccharide from this patient as a beta-galactoside substrate. The other natural beta-galactoside substrates used in this investigation were different oligosaccharides, one glycopeptide and ceramide-beta-galactosidase. The beta-galactosidase forms with acidic pH optimum towards synthetic substrate (A forms) exhibit activity towards the natural substrate (except ceramide-beta-galactoside). The "neutral" beta-galactosidase with broad substrate specificity (B form) which includes beta-glucosides had no activity towards the natural substrates used. It could also be shown that the activity towards ceramide-beta-galactoside was a third type of beta-galactosidase different from A and B forms.
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PMID:beta-D-galactosidase activities in juvenile GM1-gangliosidosis. 3 Oct 52

Human fetal tissues derived from prostaglandin-induced abortuses (9--18 wk fertilization age) have been utilized to evaluate sphingolipid composition and catabolism. Sphingolipid composition (lipid-hexose, sulfatide, and lipid-bound NANA) was assessed in fetal brain. Sphingolipid catabolism was evaluated in fetal lung and brain through the measurement of relevant acid hydrolases (arylsulfatase A, beta-galactosidase, and hexosaminidase). During the fetal period studied, the parameters of sphingolipid composition revealed variability but no consistent pattern of change. Each acid hydrolase was readily detected. Enzyme specific activities revealed no variation during the 9 fetal wk studied. Cellulose acetate electrophoresis yielded the anticipated isoenzyme patterns for each acid hydrolase with little variation during the period of study. The compositional values support current concepts of cerebral development during this period of fetal life. Together with the catabolic analyses, these studies provide normative data relative to the assessment of metabolic abnormalities during this period of fetal development.
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PMID:Sphingolipid composition and catabolism in human fetal tissues. 3 Dec 73

beta-Galactosidase (EC 3.2.1.32) was purified 80-fold from the yeast Kluyveromyces lactis induced for this enzyme by growth on lactose. When the purified enzyme was subjected to electrophoresis on an acrylamide gel in the presence of sodium dodecyl sulfate, one protein with an apparent molecular weight of 135,000 was observed. The enzyme has a sedimentation coefficient of 9.6S. This beta-galactosidase and the one from Escherichia coli are not antigenically related. Maximal enzyme activity requires Na+ and Mn2+ and a reducing agent. beta-Galactosidase has Km values of 12 to 17 and 1.6 mM for lactose and o-nitrophenyl-beta-D-galactoside, respectively. The hydrolase and transgalactosylase activities of the enzyme are similar to those of E. coli beta-galactosidase.
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PMID:Purification and properties of an inducible beta-galactosidase isolated from the yeast Kluyveromyces lactis. 3 53

Mice undergoing graft-versus-host reaction, skin grafting, and inoculation with tumor cells were tested for nonspecific resistance by intravenous challenge with Listeria monocytogenes. Peritoneal exudate macrophages from mice treated in a similar manner were tested in vitro for increased degradation of [1-14C]glucose, ability to degrade antigen/antibody complexes, ability to inhibit intracellular growth of listeria, and staining for beta-galactosidase. There was good correlation between in vivo resistance towards L. monocytogenes and in vitro inhibition of intracellular growth. There was also good correlation between increase in beta-galactosidase and in vivo resistance in mice undergoing a graft-versus-host-reaction.
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PMID:Correlation between in vivo and in vitro functional tests for activated macrophages. 3 98

Phospho-beta-galactosidase (P-beta-gal), the enzyme which catalyzes the first step in the metabolism of intracellular lactose phosphate, occurred at high specific activity in the cytoplasm in 12 of 13 strains of streptococcus mutans grown on lactose but not other carbon sources. The P-beta-gal from S. mutans SL1 was purified 13-fold using diethylaminoethyl-cellulose ion exchange and agarose A--0.5 M molecular exclusion column chromatography. The molecualr weight of the enzyme was estimated to be 40,000, and its pH optimum was 6.5 in three different buffer systems. P-beta-gal activity was inhibited by Co2+, Zn2+, and Cu2+, but other cations, ethylenediaminetetraacetic acid, orthophosphate, and fluoride had no effect upon enzyme activity. The kinetic response of P-beta-gal to a model substrate, o-nitrophenyl-beta-D-galactopyranoside-6-phosphate, obeyed Michaelis-Menten kinetics, and the Km for this substrate was 0.19 mM. In addition to being under genetic control, P-beta-gal activity was regulated by a number of biologically active metabolites. Enzyme activity was inhibited in a sigmoidal fashion by phosphoenolpyruvate. The M 0.5 V value for phosphoenolpyruvate was 2.8 mM, and the Hill coefficient (n) was 3. In addition, P-beta-gal exhibited strong inhibition by ATP, galactose-6-phosphate, and glucose-6-phosphate. In contrast to inhibition of P-beta-gal activity by phosphoenolpyruvate, the inhibition exerted by ATP, galactose-6-phosphate, and glucose-6-phosphate obeyed classical Michaelis-Menten kinetics; the Ki values for these inhibitors were 0.55, 1.6, and 4.0 mM, respectively.
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PMID:Regulation of lactose catabolism in Streptococcus mutans: purification and regulatory properties of phospho-beta-galactosidase. 3 99

beta-Glucosidase [beta-D-glucoside glucohydrolase EC 3.2.1.21] and beta-galactosidase [beta-D-galactoside galactohydrolase, EC 3.2.1.23] of Takadiastase were purified by acetone fractionation, DEAE-cellulose, and hydroxylapatite chromatography. Purity was confirmed by disc electrophoresis, ultracentrifugation and measurement of other glycosidase activities which coexisted in Takadiastase. Molecular weight of the beta-glucosidase was 218,000 by sedimentation equilibrium and 110,000-116,000 by SDS-disc electrophoresis. Molecular weight of the beta-galactosidase was 112,000 by sedimentation and 56,000-59,000 by SDS-disc electrophoresis. These values showed that both enzymes consisted of two subunits. Taka-beta-N-acetylglucosaminidase also consisted of two subunits. Both enzymes were glycoproteins containing glucosamine and neutral sugar. Stability, pH optima, isoelectric points, and some specificities were observed.
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PMID:Comparative studies of three exo-beta-glycosidases of Aspergillus oryzae. 3 73

The urinary excretion of lactate dehydrogenase, gamma-glutamyltransferase, alkaline phosphatase, arylsulphatase A, alpha-glucosidase, beta-galactosidase, trehalase, N-acetyl-beta-glucosaminidase, beta-glucuronidase, and leucine arylamidase was studied in 68 patients with biopsy-proved glomerular, 54 with interstitial renal disease and in 97 patients suffering from primary hypertension. The enzyme output of these 219 patients was compared to that of a reference population of 100 thoroughly selected healthy subjects. The highest incidence of elevated enzyme excretion was observed for N-acetyl-beta-glucosaminidase with 88% in glomerulopathies and 78% in interstitial disease, followed by beta-galactosidase. 94% of the patients with glomerular kidney disease, 90% of those with interstitial disease and about 60% of the subjects with primary benign hypertension revealed an output of at least one enzyme above upper reference limit. The highest average enzymuria occured in glomerulopathies, particularly high values in patients with the nephrotic syndrome. Application of discriminant analysis to the urinary enzyme pattern of glomerular and interstitial renal diseases resulted in an overall correct classification into the appropriate group of 89% of all patients. The discrimination between glomerular and interstitial disease was better in patients with normal renal function than in those with reduced function. Results show, that the analysis of urinary enzyme patterns may be a helpful adjunct for differential diagnosis of kidney diseases.
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PMID:Evaluation of urinary enzyme patterns in patients with kidney diseases and primary benign hypertension. 3 57

Growth of Escherichia coli strain MM6-13 (ptsI suc lacI sup), which as a suppressor of the succinate-negative phenotype, was inhibited by lactose. Cells growing in yeast extract-tryptone-sodium chloride medium (LB broth) were lysed upon the addition of lactose. In Casamino Acids-salts medium, lactose inhibited growth, but due to the high K+ content no lysis occurred. Lysis required high levels of beta-galctosidase and lactose transport activity. MM6, the parental strain of MM6-13, has lower levels of both of these activities and was resistant to lysis under these conditions. When MM6 was grown in LB broth with exogenous cyclic adenosine monophosphate, however, beta-galactosidase and lactose transport activities were greatly increased, and lysis occurred upon the addition of lactose. Resting cells of both MM6 and MM6-13 were lysed by lactose in buffers containing suitable ions. In the presence of MG2+, lysis was enhanced by 5 mM KCl and 100 mM NaCl. Higher slat concentrations (50 mM KCl or 200 mM NaCl) provided partial protection from lysis. In the absence of Mg2+, lysis occurred without KCl. Lactose-dependent lysis occurred in buffers containing anions such as sulafte, chloride, phosphate, or citrate; however, thiocyanate or acetate protected the cells from lysis. These data indicate that both cations and anions, as well as the levels of lactose transport and beta-galactosidase activity, are important in lysis.
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PMID:Lysis of Escherichia coli mutants by lactose. 4 Sep 61

1. Rat liver cells obtained by dispersion with collagenase were used to investigate the mode of entry of L-tri-iodothyronine into the cell. 2. The hormone was taken up very rapidly at 23 degrees C; the linear phase of uptake lasted for up to approx. 20 s. 3. A plot of the initial rates of uptake against different concentrations of L-tri-iodothyronine yielded a sigmoidal curve. The Eadie--Hofstee plot (v/[S]2 versus v) yielded two straight lines. The uptake component with an apparent Kt value of 86 +/- 15 pM was designated as system I, and the second uptake component with an apparent Kt of 726 +/- 11 pM as system II. The Hill plot for system I was not linear; the apparent Hill coefficient for system II was calculated to be 2.1.4. Uptake of L-tri-iodothyronine by system I was higher at pH 6.4 than at pH 7.4; system II was relatively insensitive to changes in the pH of the external medium. 5. Both systems exhibited a transition temperature at about 16 degrees C in the Arrhenius plot. The activation energies of the two systems below and above 16 degrees C were 72.8 and 47.7 and 54.4 and 33.1 J/mol respectively. 6. Inhibitors of cellular energy reduced the uptake by system I to a larger extent than that by system II. 7. Replacement of Na+ in the external medium by either K+ or choline led to uptake that followed normal Michaelis--Menten kinetics. 8. Thiol-group-blocking agents reduced the uptake of the hormone by both systems. 9. Treatment of liver cells with beta-glucosidase, Pronase and neuraminidase led to a decrease in the uptake of L-tri-iodothyronine by system I, whereas uptake by system II was decreased after treatment with phospholipase A2, beta-galactosidase. Pronase and neuraminidase. 10. The stereoisomer D-tri-iodothyronine (100--3000 pM) did not affect system I, but uptake by system II decreased with increasing concentration of D-tri-iodothyronine. Reverse L-tri-iodothyronine (2--100 pM) and L-thyroxine (100--3000 pM) did not influence uptake by either system. 11. Under identical conditions of incubation, the uptake of L-tri-iodothyronine was 3.7 times higher than binding to cytosol proteins. The binding was insensitive to metabolic inhibitors. The results suggest that cytosol proteins are not directly involved in the uptake of L-tri-iodothyronine. 12. Plasma-membrane vesicles also take up the hormone rapidly at 23 degrees C. Increasing the osmolarity of the external medium led to a decrease in the uptake of L-tri-iodothyronine by vesicles. 13. Uptake as a function of L-tri-iodothyronine concentration exhibited a sigmoidal curve. The Eadie--Hofstee plot showed two uptake components with apparent Kt values of 96.8 and 1581 pM. 14. The results of our study are consistent with a carrier-mediated translocation of the hormone into the cell.
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PMID:Uptake of L-tri-iodothyronine by isolated rat liver cells. A process partially inhibited by metabolic inhibitors; attempts to distinguish between uptake and binding to intracellular proteins. 4 20

Antisera against tetrahydronaphthalenols, which are conformationally rigid derivatives of adrenergic catecholamine, were produced in rabbits immunized with trans-5-amino-6-hydroxy-2-isopropylamino-1,2,3,4-tetrahydronaphthalene-1 -ol (I) conjugated to succinylated bovine serum albumin at the C5 position on the tetralin ring. Antisera were screened by immunodiffusion and further characterized by passive hemagglutination assay using erythrocytes sensitized with trans-I-ovalbumin conjugate and by enzyme immunoassay using trans-I-beta-galactosidase conjugate. Cross-reactivity studies indicated that the antiserum was highly specific for the tetralin structure and for substitution at the C2 position. The antiserum also selectively discriminated the stereoisomers about the C1-C2 bond. The anti-trans-I serum was used to develop EIA for trans-5-hydroxymethyl-6-hydroxy-2-isopropylamino-1,2,3,4-tetrahydronapht halene- 1-ol (IIb), which exhibited strong beta-stimulating activity fairly selective to tracheal muscle, since it recognized trans-IIb to the same degree as trans-I. The assay could detect as little as 100 pg of this compound. The mean recovery of trans-IIb added to plasma was 105%, and values for plasma trans-IIb determined by this immunoassay correlated well with those determined by gas chromatography-mass spectrometry.
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PMID:Enzyme immunoassay of a beta-adrenergic agent using beta-galactosidase as label. 4 9


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