Beta Glycosidases
Mostrando 1-12 de 32 artigos, teses e dissertações.
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1. Molecular bases of the specificity substrate of a β-glicodase / Bases moleculares da especificidade pelo substrato em β-glicosidases
The β-glycosidases of family 1 of the glycoside hydrolases (GH 1) are one of the most important groups of enzymes. These enzymes are involved in a high diversity of physiological functions. The main objective of this study was the analysis of the molecular bases of the specificity for substrate of a β-glycosidase from the larvae of Spodoptera frugi
Publicado em: 2009
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2. Purification and characterization of digestive beta-glycosidases from Spodoptera frugiperda (Lepidoptera) / Purificação e caracterização das β-glicosidases digestivas de Spodoptera frugiperda (Lepidoptera)
Foram purificadas através de uma combinação de cromatografias as duas β- glicosidases digestivas (Mr 47.000 e 50.000 - denominadas β47 e β50, respectivamente) encontradas na larva de S. frugiperda. Experimentos de competição entre substratos e modificação química mostraram que a β47 possui dois sítios ativos. Um desses sítios de
Publicado em: 1999
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3. Intracellular glycosidases of human colon Bacteroides ovatus B4-11.
Activity of various glycosidases in the intracellular enzyme fraction of Bacteroides ovatus B4-11 was investigated. During 120 h of incubation at 37 degrees C, ca. 30% of the crude hemicellulose was hydrolyzed by an intracellular enzyme fraction of strain B4-11. Xylose was the major sugar released from crude hemicellulose. Glycosidases (alpha-1,6-glucosidase
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4. Mucin degradation in human colon ecosystems. Isolation and properties of fecal strains that degrade ABH blood group antigens and oligosaccharides from mucin glycoproteins.
We previously reported that the oligosaccharide chains of hog gastric mucin were degraded by unidentified subpopulations numbering approximately 1% of normal human fecal bacteria. Here we report on the enzyme-producing properties of five strains of mucin oligosaccharide chain-degrading bacteria isolated from feces of four healthy subjects. Four were isolated
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5. Purification of glycoside hydrolases from Bacteroides fragilis.
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 foc
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6. Phosphohexosyl recognition is a general characteristic of pinocytosis of lysosomal glycosidases by human fibroblasts.
We recently presented data showing that mannose-6-phosphate was a potent competitive inhibitor of pinocytosis of human platelet beta-glucuronidase, and that treatment of "high-uptake" forms of the enzyme with alkaline phosphatase destroyed the high-uptake property of the enzyme without diminishing its catalytic activity. These data indicate that phosphate is
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7. Removal of carbohydrate from influenza A virus and its hemagglutinin and the effect on biological activities.
Treatment of influenza virus and its purified hemagglutining with glycosidases from Diplococcus pneumoniae, which included beta-galactosidase, beta-N-acetylglucosminidase, and endoglycosidase D, released amino and neutral sugars from the virus and these as well as large oligosaccharides from the purified hemagglutinin. The released glucosamine-containing oli
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8. Effect of castanospermine on the structure and secretion of glycoprotein enzymes in Aspergillus fumigatus.
Aspergillus fumigatus secretes a number of glycosidases into the culture medium when the cells are grown in a mineral salts medium containing guar flour (a galactomannan) as the carbon source. At least some of these glycosidases have been reported to be glycoproteins having N-linked oligosaccharides. In this study, we examined the effect of the glycoprotein
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9. Brain lysosomal glycosidase activity in immunosuppressed mice infected with avirulent Semliki forest virus.
Mice infected with an avirulent strain of Semliki forest virus show an increase in the activity of some of the brain lysosomal glycosidases. The increase in activity of these enzymes has been correlated with the histological, virological, and serological changes that result from the infection in the presence and absence of immunosuppression. Semliki forest v
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10. Primate cytomegalovirus glycoproteins: lectin-binding properties and sensitivities to glycosidases.
The lectin-binding properties and glycosidase sensitivities of the virion glycoproteins of primate cytomegaloviruses (CMVs) were examined. Three simian CMV (SCMV) strains, including Colburn, and four human CMV (HCMV) strains were compared. Their proteins were separated in denaturing polyacrylamide gels and electrotransferred onto nitrocellulose, and the glyc
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11. Characterisation in situ of the complex carbohydrates in rabbit oviduct using digestion with glycosidases followed by lectin binding.
Enzymatic degradation followed by lectin application was carried out on specimens of the rabbit oviduct. The sequential application of the glycosidases (neuraminidase, alpha-L-fucosidase, beta-galactosidase and alpha-mannosidase) and lectins (peanut, winged pea, wheat germ and soybean) seem promising as an effective method for characterising, in situ, the st
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12. Sequencing and expression of the Butyrivibrio fibrisolvens xylB gene encoding a novel bifunctional protein with beta-D-xylosidase and alpha-L-arabinofuranosidase activities.
A single gene (xylB) encoding both beta-D-xylosidase (EC 3.2.1.37) and alpha-L-arabinofuranosidase (EC 3.2.1.55) activities was identified and sequenced from the ruminal bacterium Butyrivibrio fibrisolvens. The xylB gene consists of a 1.551-bp open reading frame (ORF) encoding 517 amino acids. A subclone containing a 1.843-bp DNA fragment retained both enzym