Water Insoluble Glucan
Mostrando 1-12 de 70 artigos, teses e dissertações.
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1. Imunoterapia de úlceras venosas com ß-(1-3) glucana insolúvel
Uma glucana insolúvel foi isolada de fermento biológico (Saccharomyces cerevisiae), o qual foi submetido a um tratamento com base e o resíduo acidificado. Análises químicas e ressonância magnética nuclear (NMR) em uma e duas dimensões (1D e 2D) mostraram que uma -(13) glucana linear foi purificada, a qual não estava contaminada com outros carboidrat
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 28/09/2009
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2. Extração, purificação e caracterização de polissacarídeos da biomassa do fungo ascomiceto Botryosphaeria rhodina MAMB-05
The composition of the polysaccharides constituting the biomass of the ascomyceteous fungus, Botryosphaeria rhodina MAMB-05, cultivated on glucose as carbon source was investigated following separation of the exopolysaccharides (EPS). Fungal mycelial biomass was exhaustingly washed with water at room temperature until no residual sugars could be detected (ph
Publicado em: 2007
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3. Caracterização dos padrões de expressão de glucosiltransferases B e C, da proteina ligante de glucano B e de possiveis genes reguladores em genotipos distintos de Streptococcus mutans / Expression analysis of glucosyltransferases B and C, glucan-binding protein B and their putative regulatory genes in distinct genotypes of Streptococcus mutans
Streptococcus mutans, the main pathogen of dental caries, have the capacity to accumulate in the dental biofilm in the presence of sucrose, under highly acidic conditions that are responsible for teeth demineralization. The glucosyltransferases B (GtfB) and C (GtfC) produced by S. mutans are essential in this process, because catalyze the synthesis of water-
Publicado em: 2006
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4. Effect of salts on water-insoluble glucan formation by glucosyltransferase of Streptococcus mutans.
The formation of water-insoluble glucan by extracellular glucosyltransferase from Streptococcus mutans 6715 found to be greatly stimulated by various mono- or divalent cations. An enzyme preparation, obtained by ethanol fractionation, was able to catalyze the formation of water-insoluble glucan from sucrose in the presence of monovalent cations above 100mM o
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5. Purification and properties of glucosyltransferase responsible for water-insoluble glucan synthesis from Streptococcus mutans.
A glucosyltransferase responsible for water-insoluble glucan synthesis was purified from the culture fluids of Streptococcus mutans 6715-15 strain by column chromatography on Toyopearl HW-60 and subsequently on hydroxyapatite. The enzyme preparation gave a single band on analysis by polyacrylamide gel electrophoresis. The pH dependency of the activity showed
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6. Glucan-binding domain of a glucosyltransferase from Streptococcus sobrinus: isolation of a 55-kilodalton peptide from a trypsin digest of glucosyltransferase prebound to insoluble glucan.
We isolated a glucan-binding domain of water-insoluble glucan synthase (GTF-I) of Streptococcus sobrinus B13. Mild trypsin digestion of GTF-I bound to a water-insoluble glucan (IG) produced one predominant large fragment (55 kilodaltons). The fragment was easily recovered in IG precipitate. The isolated fragment had the same degree of affinity to IG as did t
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7. Characterization of an anti-glucosyltransferase serum specific for insoluble glucan synthesis by Streptococcus mutans.
An anti-glucosyltransferase serum, which synthesized 96% insoluble glucans, was prepared against a purified enzyme preparation from Streptococcus mutans strain HS6 (serotype a). This serum was examined for its effects on glucan synthesis by crude enzyme preparations from eight strains (four serotypes) of S. mutans and for the ability of these preparations to
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8. Streptococcus mutans Dextransucrase: Functioning of Primer Dextran and Endogenous Dextranase in Water-Soluble and Water-Insoluble Glucan Synthesis
The extracellular enzyme activities of Streptococcus mutans 6715 that synthesize glucans from sucrose were concentrated and partially purified by ammonium sulfate precipitation and gel permeation column chromatography. Polyacrylamide gel analysis demonstrated that all of the major proteins precipitated by ammonium sulfate were quantitatively recovered in the
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9. Insoluble glucan synthesis by Streptococcus mutans serotype c strains.
Both dextransucrase and mutansynthetase activities have been purified from the culture fluids of Streptococcus mutans GS-5 (serotype c). Although homogeneous dextransucrase preparations normally synthesize little insoluble glucan, essentially all of the glucan synthesized by this enzyme in the presence of 1.5 M (NH4)2SO4 was water insoluble. Linkage analysis
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10. Expression of gtfS is essential for normal insoluble glucan synthesis by Streptococcus downei.
The gtfI and gtfS genes of Streptococcus downei were investigated to determine the contribution of the respective enzymes to glucan production in the presence and absence of other glucosyltransferases. Extracts of Escherichia coli expressing cloned gtfS produced a short linear dextran from sucrose which could act as a primer for insoluble glucan synthesis wh
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11. Peptide sequences for sucrose splitting and glucan binding within Streptococcus sobrinus glucosyltransferase (water-insoluble glucan synthetase).
The gene encoding glucosyltransferase responsible for water-insoluble glucan synthesis (GTF-I) of Streptococcus sobrinus (formerly Streptococcus mutans 6715) was cloned, expressed, and sequenced. A gene bank from S. sobrinus 6715 DNA was constructed in vector pUC18 and screened with anti-GTF-I antibody to detect clones producing GTF-I peptide. Five immunopos
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12. Dextranases from oral bacteria: inhibition of water-insoluble glucan production and adherence to smooth surfaces by Streptococcus mutans.
The effect of dextranases (EC 3.2.1.11) from the oral isolates Actinomyces israelii and Bacteroides ochraceus on water-insoluble glucan production by the Streptococcus mutans dextransucrase (EC 2.4.1.5) and sucrose-dependent adherence to smooth glass surfaces by S. mutans was studied. Collection on membrane filters of water-insoluble polysaccharides synthesi