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Robert J. Stack - One of the best experts on this subject based on the ideXlab platform.
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Structural studies of the extracellular polysaccharide from Butyrivibrio fibrisolvens strain CF3
Carbohydrate Research, 1997Co-Authors: Fernando Ferreira, Lennart Kenne, Michael A. Cotta, Robert J. StackAbstract:Abstract The capsular polysaccharide from Butyrivibrio fibrisolvens strain X6C61 has been investigated using NMR spectroscopy, mass spectrometry, methylation methylation analysis, and partial acid hydrolysis as the main methods. The polysasccharide is composed of hexasaccharide repeating units having the following structure. The polysaccharide also contains O-acetyl groups, of which ≈70% are substituted to O-3 of the β- d -GlcpA residue.
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Structural studies of the extracellular polysaccharide from Butyrivibrio fibrisolvens strain CF3.
Carbohydrate research, 1997Co-Authors: Fernando Ferreira, Lennart Kenne, Michael A. Cotta, Robert J. StackAbstract:The structure of the Butyrivibrio fibrisolvens strain CF3 capsular polysaccharide has been investigated mainly by sugar and methylation analyses, Smith degradation, NMR spectroscopy, and mass spectrometry. The results indicate that the polysaccharide is composed of pentasaccharide repeating units having the following structure: -->4)-beta-L-Altp-(1-->4)-beta-D-Glcp-(1-->3)-4-O-[(R)-1-carboxyet hyl]-beta- D-Glcp-(1-->4)-6-O-[(R)-1-carboxyethyl]-alpha-D-Galp-(1--> 2 increases 1 beta-D-Glcp.
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Structural studies of the extracellular polysaccharide from Butyrivibrio fibrisolvens strain 49.
Carbohydrate research, 1995Co-Authors: Fernando Ferreira, Lennart Kenne, Michael A. Cotta, M Andersson, Robert J. StackAbstract:The structure of Butyrivibrio fibrisolvens strain 49 capsular polysaccharide has been investigated mainly by sugar and methylation analysis, partial chemical degradations, NMR spectroscopy, and mass spectrometry. The results suggest that the polysaccharide is composed of pentasaccharide repeating units having the following structure. [formula: see text] The polysaccharide contains O-acetyl groups, one of which is substituted to O-3 of the 4-substituted alpha-D-Galp residue, while others occur in non-stoichiometric amounts at other locations.
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Structural studies of the extracellular polysaccharide from Butyrivibrio fibrisolvens strain X6C61.
Carbohydrate research, 1993Co-Authors: M Andersson, Lennart Kenne, S Ratnayake, L Ericsson, Robert J. StackAbstract:The capsular polysaccharide from Butyrivibrio fibrisolvens strain X6C61 has been investigated using NMR spectroscopy, mass spectrometry, methylation analysis, and partial acid hydrolysis as the main methods. The polysaccharide is composed of hexasaccharide repeating units having the following structure. [formula: see text] The polysaccharide also contains O-acetyl groups, of which approximately 70% are substituted to O-3 of the beta-D-Glc pA residue.
Lennart Kenne - One of the best experts on this subject based on the ideXlab platform.
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Structural studies of the extracellular polysaccharide produced by Butyrivibrio fibrisolvens strain H10b.
Carbohydrate research, 2003Co-Authors: Lars Andersson, Michael A. Cotta, Lennart KenneAbstract:The extracellular polysaccharide produced by Butyrivibrio fibrisolvens strain H10b, when grown under strictly anaerobic conditions with glucose as carbohydrate source, has been studied by chemical and spectroscopic techniques. The results demonstrate that the polysaccharide consists of hexasaccharide repeating units with the following structure: [structure: see text] The isolated polysaccharide was found to be approximately 65% acetylated at O-2 of the 3-O-[(S)-1-carboxyethyl]-beta-D-Glcp residue. The absolute configuration of the 1-carboxyethyl groups was determined by circular dichroism.
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structural studies of the extracellular polysaccharide produced by Butyrivibrio fibrisolvens strain h10b
Carbohydrate Research, 2003Co-Authors: Lars Andersson, Michael A. Cotta, Lennart KenneAbstract:Abstract The extracellular polysaccharide produced by Butyrivibrio fibrisolvens strain H10b, when grown under strictly anaerobic conditions with glucose as carbohydrate source, has been studied by chemical and spectroscopic techniques. The results demonstrate that the polysaccharide consists of hexasaccharide repeating units with the following structure: Download : Download full-size image The isolated polysaccharide was found to be ∼65% acetylated at O-2 of the 3-O-[(S)-1-carboxyethyl]-β- d -Glcp residue. The absolute configuration of the 1-carboxyethyl groups was determined by circular dichroism.
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Structural studies of the extracellular polysaccharide from Butyrivibrio fibrisolvens strain CF3
Carbohydrate Research, 1997Co-Authors: Fernando Ferreira, Lennart Kenne, Michael A. Cotta, Robert J. StackAbstract:Abstract The capsular polysaccharide from Butyrivibrio fibrisolvens strain X6C61 has been investigated using NMR spectroscopy, mass spectrometry, methylation methylation analysis, and partial acid hydrolysis as the main methods. The polysasccharide is composed of hexasaccharide repeating units having the following structure. The polysaccharide also contains O-acetyl groups, of which ≈70% are substituted to O-3 of the β- d -GlcpA residue.
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Structural studies of the extracellular polysaccharide from Butyrivibrio fibrisolvens strain CF3.
Carbohydrate research, 1997Co-Authors: Fernando Ferreira, Lennart Kenne, Michael A. Cotta, Robert J. StackAbstract:The structure of the Butyrivibrio fibrisolvens strain CF3 capsular polysaccharide has been investigated mainly by sugar and methylation analyses, Smith degradation, NMR spectroscopy, and mass spectrometry. The results indicate that the polysaccharide is composed of pentasaccharide repeating units having the following structure: -->4)-beta-L-Altp-(1-->4)-beta-D-Glcp-(1-->3)-4-O-[(R)-1-carboxyet hyl]-beta- D-Glcp-(1-->4)-6-O-[(R)-1-carboxyethyl]-alpha-D-Galp-(1--> 2 increases 1 beta-D-Glcp.
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Structural studies of the extracellular polysaccharide from Butyrivibrio fibrisolvens strain 49.
Carbohydrate research, 1995Co-Authors: Fernando Ferreira, Lennart Kenne, Michael A. Cotta, M Andersson, Robert J. StackAbstract:The structure of Butyrivibrio fibrisolvens strain 49 capsular polysaccharide has been investigated mainly by sugar and methylation analysis, partial chemical degradations, NMR spectroscopy, and mass spectrometry. The results suggest that the polysaccharide is composed of pentasaccharide repeating units having the following structure. [formula: see text] The polysaccharide contains O-acetyl groups, one of which is substituted to O-3 of the 4-substituted alpha-D-Galp residue, while others occur in non-stoichiometric amounts at other locations.
Gang-ping Xue - One of the best experts on this subject based on the ideXlab platform.
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Transformation and expression of an anaerobic fungal xylanase in several strains of the rumen bacterium Butyrivibrio fibrisolvens.
Journal of applied microbiology, 2002Co-Authors: Kari S. Gobius, Brian P. Dalrymple, Yolande Swadling, Gang-ping Xue, James H. Aylward, Christopher S. Mcsweeney, Denis KrauséAbstract:To obtain reliable transformation of a range of Butyrivibrio fibrisolvens strains and to express a Neocallimastix patriciarum xylanase gene in the recipients. Eight strains (H17c, E14, LP1309, LP1028, AR11a, OB156, LP210B and LP461A) of Bu. fibrisolvens were transformed by the Gram-positive vector pUB110. A xylanase expression/secretion cassette containing Bu. fibrisolvens promoter and signal peptide elements fused to catalytic domain II of the N. patriciarum xylanase A cDNA (xynANp) was inserted into pUB110 to create the plasmid pUBxynA. pUBxynA was used to transform seven of the Bu. fibrisolvens strains transformed by pUB110. In strain H17c pUBxynA, which produced native xylanase, 2.46 U mg-1 total xylanase activity was produced with 45% extracellular xylanase. In strain H17c pUMSX, 0.74 U mg-1 total xylanase activity was produced with 98% extracellular xylanase. H17c pUBxynA exhibited increased (28.7%) degradation of neutral detergent fibre compared with unmodified H17c; however, progressive loss of pUBxynA was observed in long-term cultivation. A stable transformation system was developed that was applicable for a range of Bu. fibrisolvens strains and high levels of expression of a recombinant xylanase were obtained in H17c which lead to increased fibre digestion. This stable transformation system with the accompanying recombinant plasmids will be a useful tool for further investigation aimed at improving ruminal fibre digestion.
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Distribution and evolution of the xylanase genes xynA and xynB and their homologues in strains of Butyrivibrio fibrisolvens.
Applied and environmental microbiology, 1999Co-Authors: Brian P. Dalrymple, Yolande Swadling, Ingrid Layton, Kari S. Gobius, Gang-ping XueAbstract:The ruminal bacterium Butyrivibrio fibrisolvens is being engineered by the introduction of heterologous xylanase genes in an attempt to improve the utilization of plant material in ruminants. However, relatively little is known about the diversity and distribution of the native xylanase genes in strains of B. fibrisolvens. In order to identify the most appropriate hosts for such modifications, the xylanase genotypes of 28 strains from the three 16S ribosomal DNA (rDNA) subgroups of Butyrivibrio fibrisolvens have been investigated. Only 4 of the 20 strains from 16S rDNA group 2 contained homologues of the strain Bu49 xynA gene. However, these four xynA-containing strains, and two other group 2 strains, contained members of a second xylanase gene family clearly related to xynA (subfamily I). Homologues of xynB, a second previously described xylanase gene from B. fibrisolvens, were identified only in three of the seven group 1 strains and not in the group 2 and 3 strains. However, six of the group 1 strains contained one or more members of the two subfamilies of homologues of xynA. The distribution of genes and the nucleotide sequence relationships between the members of the two xynA subfamilies are consistent with the progenitor of all strains of B. fibrisolvens having contained a xynA subfamily I gene. Since many xylanolytic strains of B. fibrisolvens did not contain members of either of the xynA subfamilies or of the xynB family, at least one additional xylanase gene family remains to be identified in B. fibrisolvens.
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Cloning of a gene encoding cinnamoyl ester hydrolase from the ruminai bacterium Butyrivibrio fibrisolvens E14 by a novel method
FEMS microbiology letters, 1996Co-Authors: Brian P. Dalrymple, Yolande Swadling, D. H. Cybinski, Gang-ping XueAbstract:A gene (cinI) encoding a cinnamoyl ester hydrolase (CEH) has been isolated from the ruminal bacterium, Butyrivibrio fibrisolvens E14, using a model substrate, MUTMAC [4-methylumbelliferoyl (p-trimethylammonium cinnamate chloride)]. CinI has significant amino-acid similarities with members of a large and diverse family of hydrolases with a serine/aspartic acid/histidine catalytic triad. Our analyses identified two previously unclassified amino acid sequences, the amino-terminal domain of unknown function in XynZ from Clostridium thermocellum and XynC, an acetylxylan esterase from Caldicellulosiruptor saccharolyticus, as members of the same family of hydrolases. A previously described esterase with CEH activity, XylD from Pseudomonas fluorescens ssp. cellulosa, is not similar to CinI. CinI was expressed at high levels in the periplasmic fraction of E. coli TOPP2 and released ferulic acid from Fara [5-O-(trans-feruloyl)-arabinofuranose] prepared from wheat bran.
Harry J. Flint - One of the best experts on this subject based on the ideXlab platform.
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The Butyrivibrio fibrisolvens tet(W) Gene Is Carried on the Novel Conjugative Transposon TnB1230, Which Contains Duplicated Nitroreductase Coding Sequences
Journal of bacteriology, 2004Co-Authors: Claire M. Melville, R Brunel, Harry J. Flint, Karen P. ScottAbstract:The Butyrivibrio fibrisolvens tet(W) gene is located on the conjugative transposon TnB1230. TnB1230 encodes transfer proteins with 48 to 67% identity to some of those encoded by Tn1549. tet(W) is flanked by directly repeated sequences with significant homology to oxygen-insensitive nitroreductases. The 340 nucleotides upstream of tet(W) are strongly conserved and are required for tetracycline resistance.
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Novel Tetracycline Resistance Gene,tet(32), in the Clostridium-Related Human Colonic Anaerobe K10 and Its Transmission In Vitro to the Rumen Anaerobe Butyrivibrio fibrisolvens
Antimicrobial agents and chemotherapy, 2001Co-Authors: Claire M. Melville, Karen P. Scott, Derry K. Mercer, Harry J. FlintAbstract:A novel tetracycline resistance gene, designated tet(32), which confers a high level of tetracycline resistance, was identified in the Clostridium-related human colonic anaerobe K10, which also carries tet(W). tet(32) was transmissible in vitro to the rumen anaerobe Butyrivibrio fibrisolvens 2221(R). The predicted gene product of tet(32) has 76% amino acid identity with Tet(O). PCR amplification indicated that tet(32) is widely distributed in the ovine rumen and in porcine feces.
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High-frequency transfer of a naturally occurring chromosomal tetracycline resistance element in the ruminal anaerobe Butyrivibrio fibrisolvens.
Applied and environmental microbiology, 1997Co-Authors: Karen P. Scott, Teresa M. Barbosa, K. J. Forbes, Harry J. FlintAbstract:Butyrivibrio fibrisolvens strains resistant to tetracycline were isolated from the bovine rumen. Two of three Tcr B. fibrisolvens tested were able to donate tetracycline resistance at frequencies ranging from 10(-7) to 10(-1) per donor cell in anaerobic filter matings to a rifampin-resistant mutant of the type strain of B.fibrisolvens, 2221R. The recipient strain 2221R exhibited rapid autoaggregation, which might be a factor in the high transfer rates observed. Tcr transconjugants of B. fibrisolvens 2221R were also capable of further transferring tetracycline resistance to a fusidic acid-resistant mutant, 2221F. Comparison of genomic DNAs by pulsed-field gel electrophoresis demonstrated altered band profiles in transconjugants, consistent with the acquisition of a large mobile chromosomal element. The transferable elements from the two B. fibrisolvens donors 1.23 and 1.230 (TnB123 and TnB1230, respectively) showed the same preferred insertion site in the B. fibrisolvens 2221R chromosome and are likely to be similar, or identical, elements. Hybridization experiments showed no close relationship between TnB1230 and int-xis regions from Tn916 or Tn5253. Although DNA from the B. fibrisolvens donor strains hybridized with probes carrying tet(M) or tet(O) sequences, transconjugants were found to have acquired a distinct band that hybridized only weakly with these probes, suggesting that a second, distantly related Tcr determinant had been transferred.
Karen P. Scott - One of the best experts on this subject based on the ideXlab platform.
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The Butyrivibrio fibrisolvens tet(W) Gene Is Carried on the Novel Conjugative Transposon TnB1230, Which Contains Duplicated Nitroreductase Coding Sequences
Journal of bacteriology, 2004Co-Authors: Claire M. Melville, R Brunel, Harry J. Flint, Karen P. ScottAbstract:The Butyrivibrio fibrisolvens tet(W) gene is located on the conjugative transposon TnB1230. TnB1230 encodes transfer proteins with 48 to 67% identity to some of those encoded by Tn1549. tet(W) is flanked by directly repeated sequences with significant homology to oxygen-insensitive nitroreductases. The 340 nucleotides upstream of tet(W) are strongly conserved and are required for tetracycline resistance.
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Novel Tetracycline Resistance Gene,tet(32), in the Clostridium-Related Human Colonic Anaerobe K10 and Its Transmission In Vitro to the Rumen Anaerobe Butyrivibrio fibrisolvens
Antimicrobial agents and chemotherapy, 2001Co-Authors: Claire M. Melville, Karen P. Scott, Derry K. Mercer, Harry J. FlintAbstract:A novel tetracycline resistance gene, designated tet(32), which confers a high level of tetracycline resistance, was identified in the Clostridium-related human colonic anaerobe K10, which also carries tet(W). tet(32) was transmissible in vitro to the rumen anaerobe Butyrivibrio fibrisolvens 2221(R). The predicted gene product of tet(32) has 76% amino acid identity with Tet(O). PCR amplification indicated that tet(32) is widely distributed in the ovine rumen and in porcine feces.
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High-frequency transfer of a naturally occurring chromosomal tetracycline resistance element in the ruminal anaerobe Butyrivibrio fibrisolvens.
Applied and environmental microbiology, 1997Co-Authors: Karen P. Scott, Teresa M. Barbosa, K. J. Forbes, Harry J. FlintAbstract:Butyrivibrio fibrisolvens strains resistant to tetracycline were isolated from the bovine rumen. Two of three Tcr B. fibrisolvens tested were able to donate tetracycline resistance at frequencies ranging from 10(-7) to 10(-1) per donor cell in anaerobic filter matings to a rifampin-resistant mutant of the type strain of B.fibrisolvens, 2221R. The recipient strain 2221R exhibited rapid autoaggregation, which might be a factor in the high transfer rates observed. Tcr transconjugants of B. fibrisolvens 2221R were also capable of further transferring tetracycline resistance to a fusidic acid-resistant mutant, 2221F. Comparison of genomic DNAs by pulsed-field gel electrophoresis demonstrated altered band profiles in transconjugants, consistent with the acquisition of a large mobile chromosomal element. The transferable elements from the two B. fibrisolvens donors 1.23 and 1.230 (TnB123 and TnB1230, respectively) showed the same preferred insertion site in the B. fibrisolvens 2221R chromosome and are likely to be similar, or identical, elements. Hybridization experiments showed no close relationship between TnB1230 and int-xis regions from Tn916 or Tn5253. Although DNA from the B. fibrisolvens donor strains hybridized with probes carrying tet(M) or tet(O) sequences, transconjugants were found to have acquired a distinct band that hybridized only weakly with these probes, suggesting that a second, distantly related Tcr determinant had been transferred.
