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:3.2.1.21 (beta-glucosidase)
3,280 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. In human plasma, an enzyme is present which hydrolyzes 4-methylumbelliferyl-tetra-N-acetylchitotetraoside. The function of this enzyme is unknown. 2. We have examined whether hyaluronidase, neutral endoglucosaminidase, N-acetyl-beta-D-hexosaminidase, aspartylglucosaminidase, beta-D-glucosidase, and chitobiase could hydrolyze MU-TACT. The results obtained are detailed below. 3. A purified commercial preparation of hyaluronidase does not hydrolyze MU-TACT. 4. Substrate specificity requirements, pH optimum and subcellular localization indicate that neutral endoglucosaminidase is distinguishable from MU-TACT hydrolase. Also commercial neutral endoglucosaminidase D and H have no affinity towards MU-TACT. 5. N-Acetyl-beta-D-hexosaminidase is different from MU-TACT hydrolase for the following reasons: (a) a purified enzyme preparation does not hydrolyze MU-TACT; (b) there is no correlation in the activity of the enzymes; (c) MU-TACT hydrolase is not deficient in cells of a patient with a deficiency of total N-acetyl-beta-D-glucosaminidase; and (d) the 2 enzymes have very different chromatographic characteristics and Con A binding properties. 6. Enzyme characteristics, substrate structural requirements and a lack of correlation with MU-TACT hydrolase activity suggest that aspartylglucosaminidase, beta-D-glucosidase, and chitobiase are not involved in the hydrolysis of MU-TACT. 7. None of the enzymes which we have considered corresponds to MU-TACT hydrolase. The exact nature and the function of the enzyme remains an enigma.
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PMID:Evaluation on the hydrolysis of methylumbelliferyl-tetra-N-acetylchitotetraoside by various glucosidases. A comparative study. 843 79

Alterations in the activities of certain lysosomal enzymes such as beta-D-galactosidase, beta-D-glucosidase, beta-D-glucuronidase, alpha-L-fucosidase, N-acetyl-beta-D-glucosaminidase, cathepsins B and D were studied in serum and tissue homogenates of buccal mucosa of hamsters treated with 0.5%, 7,12-dimethylbenz[a]anthracene (DMBA) in liquid paraffin. Among the enzymes studied, the activities of beta-D-galactosidase and N-acetyl-beta-D-glucosaminidase showed significant elevation both in serum and tissue homogenates fro papilloma onwards and the elevations were progressive with the development of carcinomas. The elevations in the activities of alpha-D-fucosidase and cathepsin D were found to be significant from papillomatous tissue onwards whereas in serum they showed higher activities only in carcinoma stages. The activities of beta-D-glucosidase, beta-D-glucuronidase and cathepsin B in both serum and in tissue homogenate were elevated markedly only in carcinoma stages. It is suggested that beta-D-galactosidase and N-acetyl-beta-D-glucosaminidase may be used as diagnostic markers for premalignant and malignant lesions of oral mucosa.
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PMID:Studies of the activities of lysosomal enzymes in serum and buccal pouch tissue of hamsters during 7,12-dimethylbenz[a]anthracene-induced carcinogenesis. 862 88

The effect of different water availabilities (water activity, aw; 0.98-0.93) and time (up to 15 days) on the production of seven hydrolytic enzymes by strains of F. moniliforme and F. proliferatum during early colonisation of gamma-irradiated living maize grain were examined in this study. Both the total activity (micromol 4-nitrophenol min(-1) g(-1) maize) and specific activity (nmol 4-nitrophenol min(-1) microg(-1) protein) were quantified using chromogenic p-nitrophenyl substrates. The dominant three enzymes produced by the fungi on whole colonised maize kernels were alpha-D-galactosidase, beta-D-glucosidase, and N-acetyl-beta-D-glucosaminidase. The other four enzymes were all produced in much lower total amounts and in terms of specific activity (beta-D-fucosidase, alpha-D-mannosidase, beta-D-xylosidase and N-acetyl-alpha-D-glucosaminidase), similar to that in uncolonised control maize grain. There were significant increases in the total production of the three predominant enzymes between 3-15 days colonisation, and between 3-6 days in terms of specific activity when compared to untreated controls. The total and specific activity of the alpha-D-galactosidase, beta-D-glucosidase and N-acetyl-beta-D-glucosaminidase, were maximum at 0.98 aw with significantly less being produced at 0.95 and 0.93 aw, with the exception of the total activity of alpha-D-galactosidase which was similar at both 0.95 and 0.93 aw. Single factors (time, aw, and inoculation treatment), two- and three- way interactions were all statistically significant for the three dominant enzymes produced except for specific activity of beta-D-glucosidase (two and three-way interactions) and for total activity of alpha-D-galactosidase in the time x aw treatment. This study suggests that these hydrolytic enzymes may play an important role in enabling these important fumonisin-producing Fusarium spp. to rapidly infect living maize grain over a wide aw range.
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PMID:Effect of water activity on hydrolytic enzyme production by Fusarium moniliforme and Fusarium proliferatum during colonisation of maize. 972 89

The erythrocyte membrane in 71 patients with type 2 diabetes mellitus was assessed for glycohydrolase activity: N-acetyl-beta-D-glucosaminidase, beta-D-glucuronidase, alpha- and beta-D-galactosidase, alpha- and beta-D-glucosidase, alpha-D-mannosidase, and alpha-L-fucosidase. Only beta-D-glucuronidase, alpha-D-glucosidase, and beta-D-glucosidase showed markedly elevated levels with respect to the controls regardless of the presence of complications. Among the examined patients, those with good metabolic control (not yet submitted to any therapy) showed the same enzyme levels as the reference subjects, while the levels in patients with unsatisfactory metabolic control (treated with oral hypoglycemic and/or insulin) significantly differed from the control levels. For alpha-D-glucosidase and beta-glucosidase, a correlation with glycemia and the parameters of metabolic control was also evidenced. Alterations of beta-D-glucuronidase, alpha-D-glucosidase, and beta-D-glucosidase were also ascertained in the plasma of the same diabetic patients according to the literature; each enzyme correlated with the other, either in plasma or in the erythrocyte membrane. This study shows a correlation between plasma and erythrocyte membrane levels for these three enzymes. The strict parallelism of the glycohydrolases in the two different compartments provides a profile of these enzymes in the pathology of diabetes.
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PMID:Alterations in the activity of several glycohydrolases in red blood cell membrane from type 2 diabetes mellitus patients. 1042 Dec 18

Activity of the following glycosidases was detected in the plasma of the freshwater snail Biomphalaria glabrata: beta-D-fucosidase, beta-D-glucosidase, beta-D-galactosidase, beta-D-mannosidase, beta-D-glucuronidase, N-acetyl-beta-D-galactosaminidase, N-acetyl-beta-D-glucosaminidase, and lysozyme. At the physiological pH (7.2-7.4) of snail haemolymph, enzymatic activity was about 10-50% of the maximum activity at each enzyme's respective acid pH-optimum. Schistosome-susceptible B. glabrata showed lower plasma protein concentration and significantly lower enzymatic activities (U/mg protein) than schistosome-resistant snails. Changes in glycosidase activity levels correlate with the progress of infection. After successful schistosome invasion, activities of plasma glycosidases but not the concentration of total plasma proteins increased significantly during the first 2 days in both snail strains. Thus, most tegumental glycoproteins of schistosome larvae can be altered by humoral host glycosidases. The detection of only very low activities of hexosaminidases leads to the hypothesis that GalNAc/GlcNAc may be involved in the process of non-self recognition. At 4 days post-infection, glycosidase activities were identical or slightly below the levels found in naive snails. At this time of infection the parasite is encapsulated and destroyed by haemocytes of resistant snails. In susceptible snails, however, the schistosomes have transformed into sporocysts and will complete their life-cycle without eliciting effective defence reactions. After > 30 days post-infection, when cercariae are fully developed in susceptible snails, plasma protein concentration decreased significantly, whereas glycosidase activities were elevated.
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PMID:Glycosidase activities in plasma of naive and schistosome-infected Biomphalaria glabrata (Gastropoda). 1063 17

The membrane anchoring of the following glycohydrolases of human erythrocyte plasma membranes was investigated: alpha- and beta-D-glucosidase, alpha- and beta-D-galactosidase, beta-D-glucuronidase, N-acetyl-beta-D-glucosaminidase, alpha-D-mannosidase, and alpha-L-fucosidase. Optimized fluorimetric methods for the assay of these enzymes were set up. Treatment of the ghost preparation with 1.0 mol/l (optimal concentration) NaCl caused release ranging from 4.2% of alpha-D-glucosidase to 70% of beta-D-galactosidase; treatment with 0.4% (optimal concentration) Triton X-100 liberated 5.1% of beta-D-galactosidase to 89% of alpha-D-glucosidase; treatment with 1.75% (optimal concentration) octylglucoside yielded solubilization from 6.3% of beta-D-galactosidase to 85% of alpha-D-glucosidase. Treatment with phosphoinositide-specific phospholipase C caused no liberation of any of the studied glycohydrolases. These results are consistent with the notion that the above glycohydrolases are differently anchored or associated with the erythrocyte plasma membrane, and provide the methodological basis for inspecting the occurrence of these enzymes in different membrane microdomains.
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PMID:Membrane anchoring and surface distribution of glycohydrolases of human erythrocyte membranes. 1080 66

Fertilization in Bufo arenarum requires the sperm to penetrate the egg envelopes. The incubation of isolated vitelline envelopes with sperm induces the acrosome reaction, releasing proteases and glycosidases to the media. In the present work N-acetyl-beta-D-glucosaminidase, beta-D-galactosidase, beta-D-glucosidase, alpha-D-mannosidase, alpha-L-fucosidase, and alpha-D-glucosidase activities are measured in spermatozoa. N-acetyl-beta-D-glucosaminidase is the major sperm glycosidase activity assayed. However, N-acetyl-beta-D-galactosamine show competitive inhibitory effect. The glycosidase pH optimum is 3.5 being inhibited at pHs higher than 7.5. In our study, N-acetyl-beta-D-glucosaminidase is the only glycosidase that in vitro binds to vitelline envelopes in conditions that resemble natural fertilization media. The isolation of the active enzyme will allow studies of its role in fertilization. The enzyme has been purified in a two-step procedure. After native gel electrophoresis, the activity-stained band was cut out and the eluted enzyme was finally subjected to ConA-sepharose chromatography. In SDS-PAGE, the denatured enzyme migrates as a single band with a molecular mass of 45 kDa. Furthermore, analysis by size-exclusion on HPLC showed a peak of activity at around 45 kDa. Preliminary localization studies showed higher relative activity in the acrosomal content. In addition, 10% of the N-acetyl-beta-D-glucosaminidase activity was associated with the reacted sperm. By in vitro fertilization assay, it was observed that the inhibition of the enzyme results in the inhibition of fertilization. This last study shows that N-acetyl-beta-D-glucosaminidase plays an important role in toad fertilization.
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PMID:Purification and biological characterization of N-acetyl beta-D glucosaminidase from Bufo arenarum spermatozoa. 1098 20

Volatile profiles and hydrolytic enzyme production by one non-mycotoxigenic and three mycotoxigenic strains of Fusarium moniliforme and F. proliferatum, grown in vitro for up to 96 h on a grain medium at 25 degrees C/0.95 water activity, were examined for differentiation of isolates. After spore lawn inoculation, measurements were made after 48, 72 and 96 h by sampling the head space above cultures with an electronic nose system using a 14 sensor surface polymer array, and by extraction and quantification of hydrolytic enzymes. There was good reproducibility of volatile patterns between replicates of the same treatment. Principal component analysis indicated that discrimination could be achieved between the uninoculated controls, the non-mycotoxigenic strain and the mycotoxin-producing strains for both species after 48 h. The total and specific activity of three out of seven enzymes (beta-D-glucosidase, alpha-D-galactosidase and N-acetyl-beta-D-glucosaminidase) were found to increase significantly in the non-mycotoxigenic when compared with the toxigenic strains of both species after 72 h. Activities of the others (beta-D-fucosidase, alpha-D-mannosidase, beta-D-xylosidase and N-acetyl-alpha-D-glucosaminidase) were not significantly different between strains. The study has shown for the first time that it is possible to differentiate between mycotoxigenic and non-mycotoxigenic strains of such spoilage fungi based on their volatile production patterns using an electronic nose system. These results have significance in the development of methods for the early detection of toxin-producing spoilage moulds in the food industry.
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PMID:Detection and differentiation between mycotoxigenic and non-mycotoxigenic strains of two Fusarium spp. using volatile production profiles and hydrolytic enzymes. 1111 57

Disturbed metabolism of glycosaminoglycans (GAGs) has been proposed to play an important role in the pathogenesis of late diabetic complications. The effect of diabetic complications and metabolic control on both total serum GAGs content and the serum activity of lysosomal glycosidases (N-acetyl-beta-D-glucosaminidase, alpha-L-fucosidase, beta-D-galactosidase, and alpha-D-mannosidase) contributing to GAGs degradation, was investigated in 48 patients with type 2 diabetes mellitus. The activity of beta-D-glucosidase and acid phosphatase, the lysosomal enzymes unrelated to GAGs metabolism, was determined for comparison. The elevated serum total GAG concentration in diabetic patients was strongly and positively influenced by poor metabolic compensation of diabetes and the presence of vascular complications. A similar tendency has been shown in regard to the activity of enzymes involved in GAG degradation, especially N-acetyl-beta-D-glucosaminidase, alpha-L-fucosidase and beta-D-galactosidase. Furthermore, the total serum GAG concentrations, as well as the activity of lysosomal enzymes involved in the extracellular matrix degradation, closely followed metabolic compensation, regardless of diabetic vascular complications. Thus, we suggest that increased values of the investigated parameters may indicate the degree of endothelial cell dysfunction and may be useful to predict the development of diabetic vascular pathology.
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PMID:Alterations of glycosaminoglycan metabolism in the development of diabetic complications in relation to metabolic control. 1617 71

The present study was designed to evaluate the possible beneficial effect of lipoic acid in preventing the renal damage induced by cyclosporine A in rats. Male albino rats of Wistar strain were divided into four groups and treated as follows. Two groups received cyclosporine A by oral gavage (25 mg/kg/body weight) for 21 days to induce nephrotoxicity, one of which simultaneously received lipoic acid treatment (20 mg/kg body weight) for 21 days. A vehicle (olive oil) and a lipoic acid drug control were also included. Cyclosporine A induced renal damage was evident from the decreased activities of tissue marker enzymes (alkaline phosphatase, acid phosphatase, lactate dehydrogenase, aspartate transaminase and alanine transaminase) and decreased activities of ATPases (Na+, K+-ATPase, Ca2+-ATPase and Mg2+ ATPase). An apparent increase in the levels of serum constituents (urea, uric acid and creatinine) and urinary marker enzymes (N-acetyl-beta-D-glucosaminidase, beta-glucosidase, beta-galactosidase, cathepsin-D and gamma-glutamyl transpeptidase) along with significant decline in creatinine clearance were seen in the cyclosporine treated rats, which was reversed upon treatment with lipoic acid. Ultrastructural observations were also in agreement with the above abnormal changes. Lipoic acid effectively reverted these abnormal biochemical changes and minimized the morphological lesions in renal tissue. Hence, this study clearly exemplifies that lipoic acid might be an ideal choice against cyclosporine A induced cellular abnormalities.
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PMID:Therapeutic efficacy of DL-alpha-lipoic acid on cyclosporine A induced renal alterations. 1761 14


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