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)

A total of 50 different strains from clinical specimens and/or from experimental surgery were typified. The Staphylococcus genus was subdivided according to minimal test results for Staphylococcus genus differentiation into 3 groups: A. the coagulase-positive/novobiocin-susceptible species; B. the coagulase-negative/novobiocin-resistant species and C. the coagulase-negative/novobiocin-susceptible species. Species belonging to the different groups were differentiated by means of minimal biochemical tests readily available to all clinical bacteriology laboratories. To evaluate the predictive value of the procedure employed, the following strains were used as unknown: S. capitis, S. simulans, S. hominis, S. warneci, S. intermedius, S hyicus subsp. hycus, S hyicus subsp. chromogenes and S. haemolyticus. Results indicated that, for the coagulase-positive/novobiocin-susceptible group, the production of pigment and acetoin plus beta-galactosidase were sufficient for interspecies differentiation. For the coagulase-negative/novobiocin-resistant group, urease and phosphatase activity plus production of acid from xylose proved to be sufficient. The coagulase-negative/novobiocin-susceptible group required the greatest number of tests, due to phenotypical variability of species, including: reduction of nitrates; production of acetoin; use of arginine and the production of acid from maltose and/or trehalose. Preliminary findings justify routine application of these minimal tests for Staphylococcus genus differentiation.
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PMID:[Minimal biochemical tests for interspecies identification in the Staphylococcus genus]. 307 5

The reversion reactions of beta-galactosidase (Escherichia coli) produced beta-galactosyl-galactoses and beta-galactosyl-glucoses. About 10 beta-galactosyl-galactose and 10 beta-galactosyl-glucose gas-liquid chromatographic peaks were detected and it is thus very likely that every possible isomer of beta-galactosyl-galactose and beta-galactosyl-glucose was formed by the reversion reactions (taking into account both anomers for each isomer). The presence of lactose and allolactose among the beta-galactosyl-glucoses was confirmed with standards. An important finding relating to the role of allolactose as an inducer of the lac operon was that allolactose (beta-D-galactosyl-(1----6)-D-glucose) was the only disaccharide formed initially, and at equilibrium it was present in the largest amount (50%). Obviously the enzyme is specific in its ability to form allolactose, and allolactose is the most stable beta-galactosyl-glucose, both important inducer properties. The equilibrium constant (concentration of disaccharides divided by the concentration of reactants at equilibrium) of the reaction was about 9.5 mM-1. This is the first report of an equilibrium constant for the beta-galactosidase reaction. Of mechanistic significance is the fact that only three compounds were able to replace D-galactose as a reversion reactant. Two of these (L-arabinose and D-fucose) had alterations at carbon 6. The 6 position, therefore, is not essential for reactivity. The third compound was D-galactal. Any other sugars tested (even with very minor changes relative to D-galactose) did not react. Of special consequence is the 2 position. The results strongly suggest that there has to be either an equatorial hydroxyl at the 2 position of a sugar or a special reactivity (as with D-galactal) in order for the enzyme to catalyze the beta-galactosidase reaction.
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PMID:Reversion reactions of beta-galactosidase (Escherichia coli). 308 79

The activities of the enterocyte brush border enzymes lactase (beta-D galactoside galactohydrolase, EC 3.2.1.23) and sucrase (sucrose alpha-D glucohydrolase, EC 3.2.1.48) were measured at set percentage lengths along the small intestines of 112 piglets killed between 21 and 32 days of age. The influences on these activities of consumption of creep feed and of weaning were recorded. Weaning at three weeks old resulted in large, rapid reductions in lactase activity at most sites along the small intestine; sucrase activity declined temporarily and then recovered. Minimum values were recorded about four to five days after weaning. Similar changes were observed whether or not creep feed was consumed before weaning. Continued consumption of creep feed by unweaned pigs over the 21 to 32 day period also produced small but significant reductions in lactase activities. The large loss of digestive enzyme activities at brush borders in weaned animals coincided with a reduced ability to absorb xylose and to checks in growth rate in otherwise healthy piglets.
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PMID:Influence of creep feeding and weaning on brush border enzyme activities in the piglet small intestine. 308 80

A scheme is proposed for biotyping Gardnerella vaginalis, based on detection of hippurate hydrolysis, beta-galactosidase (ONPG) and lipase, and fermentation of arabinose, galactose and xylose. Seventeen biotypes were found among 197 strains from asymptomatic women and patients with bacterial vaginosis (non-specific vaginitis). The distribution of biotypes was similar in both populations but some biotypes were found more frequently in patients. The proposed scheme is compared with those previously described.
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PMID:A modified scheme for biotyping Gardnerella vaginalis. 308 81

Thirty Streptococcus faecalis isolates from mixed dental plaque samples were classified into four groups on the basis of biotype, tetracycline susceptibility, phage type and serotype combinations. The organisms were from patients on haemodialysis, from staff of the dialysis unit, and from controls. Three biotypes were distinguished by seven biochemical tests: production of acid from inositol, sucrose and xylose; rapid or delayed production of acid from sorbitol; gelatin liquefaction; and production of alkaline phosphatase and beta-galactosidase. With a set of eight typing antisera for S. faecalis, 15 strains were non-typable, 12 were serotype 1 and three were serotype 19. With a set of 17 bacteriophages specific for S. faecalis, all of the oral isolates were typable; 40% were lysotype I1 and the remainder lysotype V6b. On the basis of biotype-serotype-phage-type combinations, indications of possible spread of strains between haemodialysis patients and dialysis unit staff were obtained. Biotyping and serotyping of 13 German isolates of S. faecalis of phage type I1 from four clinical sources and tripartite typing of three control strains provided additional evidence for the potential of biotyping in distinguishing between strains of identical serotype and phage type. One oral isolate of S. faecium was of phage type XX. None of the oral isolates of S. faecalis, of which 14 exhibited delayed sorbitol fermentation, reacted with group-G streptococcal grouping reagents or antiserum. Slow sorbitol fermentation does not appear to be a definitive phenotypic marker for S. faecalis strains possessing antigens that react with both group-D and group-G grouping reagents.
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PMID:Biotyping, serotyping and phage typing of Streptococcus faecalis isolated from dental plaque in the human mouth. 310 45

Human urinary chondroitin sulfates were isolated by precipitation with cetylpyridinium chloride of the non-dialyzable fraction of pooled urine, followed by ethanol fractionation and successive enzymic digestions with neuraminidase and mucopolysaccharides. Further purification was achieved by Dowex-1 chromatography with stepwise elution by increasing the concentration of NaCl at intervals of 0.25 M from 0.75 M to 1.5 M. The chondroitin sulfates thus obtained were characterized by the analysis and quantification on of carbohydrate, amino acid and sulfate, and by electrophoresis on cellulose acetate membrane. Then reducing terminals were identified by gas liquid chromatographic analyses of the acetyl and butaneboronate derivatives of hydrolysates, after reduction of the reducing terminals with sodium borohydride. About 22.8% of the urinary chondroitin sulfate in the 1.5 M fraction was peptide-bound, and the remainder was peptide-free, with xylose (29.8%), galactose (23.6%) and glucuronic acid (18.7%) at the reducing terminal. The amount of peptide-free chondroitin sulfate with xylose and galactose at its reducing terminals in the 0.75 M-, 1.0 M-, 1.25 M- and 1.5 M-fractions increased in the order described in parallel with the increase of sulfation and the decrease of peptide content. It was thus suggested that the endo-types of beta-xylosidase, beta-galactosidase and beta-glucuronidase acted on the carbohydrate-peptide linkage region of proteo-chondroitin sulfate in the tissues and produced various types of urinary chondroitin sulfate with heterogeneity at reducing terminals.
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PMID:Heterogeneity of reducing terminals of urinary chondroitin sulfates. 310 93

The biochemical properties of 39 strains of Haemophilus avium from chickens were determined. All the strains produced acid from fructose, galactose, glucose and mannose but not from lactose. Variable reactions were found for arabinose, maltose, mannitol, sorbitol, trehalose and xylose. No strains showed urease activity or produced indole, while beta-galactosidase and/or ornithine decarboxylase activity was present in some strains. This variability allowed the recognition of 15 biochemical biovars including some not previously recognized in H. avium. Only 25 (64%) of the H. avium strains could be assigned to the three species (Pasteurella avium, P. volantium and Pasteurella species A) recently proposed to replace H. avium.
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PMID:Biochemical properties of catalase-positive avian haemophili. 315 Dec 6

One hundred twenty-seven isolates of Aeromonas comprising the three currently recognizable species (A. hydrophila, A. sobria, and A. caviae) were evaluated for biochemical and exoenzymatic properties. Aeromonas species were generally (greater than 90%) characterized as gram-negative fermentative rods that were oxidase-, catalase-, and beta-galactosidase-positive, produced arginine dihydrolase, and failed to decarboxylate ornithine. More than 95% of all isolates tested failed to grow on 6.5% salt or thiosulfate-citrate bile salts agar and were resistant to the vibriostatic agent 0/129. Most Aeromonas species produced acid from hexoses while failing to ferment alcoholic sugars or trisaccharides. In exoenzymatic studies, Aeromonas species were uniformly found to produce several exoenzymes, including amylase, DNase, RNase, esterase, lipase, gelatinase, protease, fibrinolysin, and chitinase. Within the genus, a number of biochemical and enzymatic properties were found to be associated with one or more of the taxonomically recognizable species. These properties included glycoside utilization, Heiberg grouping based upon fermentation of arabinose, sucrose, and mannose, and the elaboration of several extracellular enzymes (elastase, hemolysin, lecithinase, phosphatase). In addition, phenotypic markers previously associated with enterotoxigenic Aeromonas isolates were almost exclusively found among A. hydrophila and A. sobria species, suggesting that these species are the major enteric pathogens.
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PMID:Biochemical and exoenzymatic properties of Aeromonas species. 388 8

Human urinary chondroitin sulfate isolated from the cetylpyridinium chloride-complex of the non-dialyzable fraction of the pooled urine was subjected to ethanol fractionation, successive enzymic digestion with neuraminidase and mucopolysaccharidases, and anion exchange chromatography. The gas liquid chromatographic analyses of the acetyl and butaneboronic acid ester derivatives of the reduced terminal sugar units after treatment with sodium borohydride plus hydrolysis revealed that 42% of the urinary chondroitin sulfate was bound to peptide through xylose. The reducing terminal sugar units of the peptide-free form consisted of 34.6% of xylose, 22.4% of galactose, 16.4% of glucose of unknown origin and 26.6% of glucuronic acid. These observations showed that the xyloside, galactoside and glucuronide linkages at non-terminal sites of carbohydrate chains of chondroitin sulfate were cleaved in tissues. It was thus suggested that the endo-types of beta-xylosidase, beta-galactosidase and beta-glucuronidase, which act on proteochondroitin sulfate are present in tissues.
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PMID:Reducing terminals of urinary chondroitin sulfate. 393 89

Catabolite repression of tryptophanase was studied in detail under various conditions in several strains of Escherichia coli and was compared with catabolite repression of beta-glactosidase. Induction of tryptophanase and beta-galactosidase in cultures grown with various carbon sources including succinate, glycerol, pyruvate, glucose, gluconate, and arabinose is affected differently by the various carbon sources. The extent of induction does not seem to be related to the growth rate of the culture permitted by the carbon source during the course of the experiment. In cultures grown with glycerol as carbon source, preinduced for beta-galactosidase or tryptophanase and made permeable by ethylenediaminetetraacetic acid (EDTA) treatment, catabolite repression of tryptophanase was not affected markedly by the addition of cAMP (3',5'-cyclic adenosine monophosphate). Catabolite repression by glucose was only partially relieved by the addition of cAMP. In contrast, under the same conditions, cAMP completely relieved catabolite repression of beta-galactosidase by either pyruvate or glucose. Under conditions of limited oxygen, induction of tryptophanase is sensitive to catabolite repression; under the same conditions, beta-galactosidase induction is not sensitive to catabolite repression. Induction of tryptophanase in cells grown with succinate as carbon source is sensitive to catabolite repression by glycerol and pyruvate as well as by glucose. Studies with a glycerol kinaseless mutant indicate that glycerol must be metabolized before it can cause catabolite repression. The EDTA treatment used to make the cells permeable to cAMP was found to affect subsequent growth and induction of either beta-galactosidase or tryptophanase much more adversely in E. coli strain BB than in E. coli strain K-12. Inducation of tryptophanase was reduced by the EDTA treatment significantly more than induction of beta-galactosidase in both strains. Addition of 2.5 x 10(-3)m cAMP appeared partially to reverse the inhibitory effect of the EDTA treatment on enzyme induction but did not restore normal growth.
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PMID:Catabolite repression of tryptophanase in Escherichia coli. 432 48


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