Xylans
Mostrando 13-21 de 21 artigos, teses e dissertações.
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13. A Partial Characterization of an Autolytically Solubilized Cell Wall Glucan 1
Incubation of purified cell wall fragments from corn (Zea mays) coleoptiles results in solubilization of some of the wall dry matter. The portion of the weight loss due to enzymatic autolysis is due mainly to solubilization of a glucan and, to a small extent, to liberation of free glucose. No other carbohydrate wall components or sugars other than glucose ar
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14. Identification of two distinct Bacillus circulans xylanases by molecular cloning of the genes and expression in Escherichia coli.
Two genes coding for xylanase synthesis in Bacillus circulans were cloned and expressed in Escherichia coli. After digestion of genomic DNA from Bacillus circulans with EcoRI and PstI, the fragments were ligated into the corresponding sites of pUC19 and transformed into Escherichia coli. Restriction enzyme mapping of the two inserts coding for xylanase activ
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15. Purification and characterization of two thermostable acetyl xylan esterases from Thermoanaerobacterium sp. strain JW/SL-YS485.
Two acetyl esterases (EC 3.1.1.6) were purified to gel electrophoretic homogeneity from Thermoanaerobacterium sp. strain JW/SL-YS485, an anaerobic, thermophilic endospore former which is able to utilize various substituted xylans for growth. Both enzymes released acetic acid from chemically acetylated larch xylan. Acetyl xylan esterases I and II had molecula
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16. Purification and Characterization of an α-l-Arabinofuranosidase from Butyrivibrio fibrisolvens GS113
An α-l-arabinofuranosidase (EC 3.2.1.55) was purified from the cytoplasm of Butyrivibrio fibrisolvens GS113. The native enzyme had an apparent molecular mass of 240 kDa and was composed of eight polypeptide subunits of 31 kDa. The enzyme displayed an isoelectric point of 6.0, a pH optimum of 6.0 to 6.5, a pH stability of 4.0 to 8.0, and a temperature optimu
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17. A xylan hydrolase gene cluster in Prevotella ruminicola B(1)4: sequence relationships, synergistic interactions, and oxygen sensitivity of a novel enzyme with exoxylanase and beta-(1,4)-xylosidase activities.
Two genes concerned with xylan degradation were found to be closely linked in the ruminal anaerobe Prevotella ruminicola B(1)4, being separated by an intergenic region of 75 nucleotides. xynA is shown to encode a family F endoxylanase of 369 amino acids, including a putative amino-terminal signal peptide. xynB encodes an enzyme of 319 amino acids, with no ob
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18. Purification and characterization of two arabinofuranosidases from solid-state cultures of the fungus Penicillium capsulatum.
Two arabinofuranosidases, termed Ara I and Ara II, from solid-state cultures of Penicillium capsulatum were purified to apparent homogeneity as judged by electrophoresis and isoelectric focusing. Each enzyme is a single subunit glycoprotein, and they have M(r)s and pIs of 64,500 and 4.15 (Ara I) and 62,700 and 4.54 (Ara II), respectively. Ara I is most activ
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19. Novel Features of the Polysaccharide-Digesting Gliding Bacterium Flavobacterium johnsoniae as Revealed by Genome Sequence Analysis▿ †
The 6.10-Mb genome sequence of the aerobic chitin-digesting gliding bacterium Flavobacterium johnsoniae (phylum Bacteroidetes) is presented. F. johnsoniae is a model organism for studies of bacteroidete gliding motility, gene regulation, and biochemistry. The mechanism of F. johnsoniae gliding is novel, and genome analysis confirms that it does not involve w
American Society for Microbiology (ASM).
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20. Evidence for Temporal Regulation of the Two Pseudomonas cellulosa Xylanases Belonging to Glycoside Hydrolase Family 11
Pseudomonas cellulosa is a highly efficient xylan-degrading bacterium. Genes encoding five xylanases, and several accessory enzymes, which remove the various side chains that decorate the xylan backbone, have been isolated from the pseudomonad and characterized. The xylanase genes consist of xyn10A, xyn10B, xyn10C, xyn10D, and xyn11A, which encode Xyn10A, Xy
American Society for Microbiology.
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21. Regulation of Endo-Acting Glycosyl Hydrolases in the Hyperthermophilic Bacterium Thermotoga maritima Grown on Glucan- and Mannan-Based Polysaccharides
The genome sequence of the hyperthermophilic bacterium Thermotoga maritima encodes a number of glycosyl hydrolases. Many of these enzymes have been shown in vitro to degrade specific glycosides that presumably serve as carbon and energy sources for the organism. However, because of the broad substrate specificity of many glycosyl hydrolases, it is difficult
American Society for Microbiology.