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)

About 1200 strains of microorganisms were screened including fungi, actinomyces, and bacteria, in which 237 strains producing the enzyme desired. The results showed that the beta-GlcNAcase and beta-GalNAcase always co-existed in one strain, though may be in different ratio. From strains mentioned above the authors screened out a potent beta-N-acetylhexosaminidase producing strain, Aspergillus tamarii S215, from the soil sample. The optimal conditions for enzyme production were as follows: the microorganisms was inoculated in a 5% wheat bran suspension, cultured at 28-30 degrees C on shaker for 5-6 days. The productivity can be moderately enhanced by the addition of cellobiose or glucosamine or galactosamine or by the extra supplement of (NH4)2SO4 and NH4NO3 as N sources. In the culture filtrate of Asp. tamarii, the alpha, (beta)-galactosidase, beta-glucosidase, alpha-mannosidase and beta-fucosidase were also found.
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PMID:[Screening of beta-N-acetylhexosaminidase forming strains and conditions for enzyme production]. 214 44

The group O streptococcal group antigen was shown to be a polysaccharide located in the cell wall of the organism. The antigen could be extracted by one of several methods: (i) 0.5 n NaOH at 37 C, (ii) phenol-water (50:50) at 68 C, (iii) 0.2 n HCl at 100 C, or (iv) 10% trichloroacetic acid at 4 C. The last method yielded more polysaccharide with less protein contamination. The polysaccharide was purified on diethylaminoethyl-Sephadex A-25 and Sephadex G-200. It was composed of two-thirds glucosamine and galactosamine, and the remainder glucose plus galactose. Rhamnose, glycerol, ribitol, and muramic acid were absent. Total phosphorus and amino acids were each less than 0.1%. N-Acetyl-beta-d-glucosamine exerted a strong inhibition of the precipitin reaction and is considered the immunodominant sugar. Glucosamine and glucose possessed a partial inhibitory activity. Galactose and galactosamine were essentially negative. No evidence of cross-reactivity was found between the O polysaccharide and group A and L polysaccharides, and group A and Staphylococcus aureus teichoic acids, which posesss N-acetylglucosamine specificity. The release of limited quantities of N-acetyl-glucosamine from its terminal location by enzyme, and glucose by acid hydrolysis, indicates a limited number of side chains in the O antigen. The glucosamine is in acid-stable linkage in the polysaccharide. Glucose was not released by beta-glucosidase and probably does not occupy a terminal position. The O antigen is the only known streptococcal polysaccharide antigen which does not contain rhamnose. The effect of these factors on the immunological specificity is discussed. O serum, after adsorption with the purified polysaccharide, was used to demonstrate the presence of protein antigens in acid extracts of cells from each of the nine strains examined. These antigens may represent type antigens. Two of these strains, originally described as group O, did not contain the O polysaccharide.
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PMID:Chemical composition and immunological specificity of the streptococcal group O cell wall polysaccharide antigen. 462 49

The formation and excretion of beta-glucosidase from Trichoderma pseudokoningii was studied during growth on different carbon sources. The enzyme was present under all conditions examined, but increased activity was found during growth on carbon sources favouring slow growth. Two different patterns of beta-glucosidase excretion were observed: on carbon sources allowing fast growth a relatively high percentage of total activity was found in the culture fluid, which decreases as the culture grows older, but which increases again during the phase of cell lysis; on carbon sources favouring slow growth, excretion is initially low, but commences at later culture stages. Changes in cell wall composition and cell wall lytic enzyme activities associated with the cell walls were examined during phases of high and low ratios of extracellular to cell-wall bound beta-glucosidase activities. With no component of the cell wall (chitin, alpha-glucan, beta-glucan, galactosamine) could correlation with beta-glucosidase excretion be identified. Among a number of cell-wall lytic, cell-wall associated enzymes (alpha-glucanases, beta-glucanases, glucosaminidase, galactosaminidase), beta-1.3-glucanase activity correlated well with the excretion of beta-glucosidase. The results suggest a possible role of beta-1.3-glucanases in the mechanism of release of beta-glucosidase from cell walls of T. pseudokoningii; this is discussed.
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PMID:beta-Glucosidase excretion by Trichoderma pseudokoningii: correlation with cell wall bound beta-1.3-glucanase activities. 681 29

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