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Bacteroides fragilis nctc

Jessica V Pierce, Harris D Bernstein
Enterotoxigenic (ETBF) strains of Bacteroides fragilis are the subset of strains that secrete a toxin called fragilysin (Bft). Although ETBF strains are known to cause diarrheal disease and have recently been associated with colorectal cancer, they have not been well characterized. By sequencing the complete genome of four ETBF strains, we found that these strains exhibit considerable variation at the genomic level. Only a small number of genes that are located primarily in the Bft pathogenicity island (BFT PAI) and the flanking CTn86 conjugative transposon are conserved in all four strains and a fifth strain whose genome was previously sequenced...
2016: PloS One
Samir Ghosh, Sharmeen Nishat, Peter R Andreana
A highly efficient and stereocontrolled synthesis of an aminooxy derivative of the tetrasaccharide repeating unit of a rhamnose-rich polysaccharide isolated from the cell envelop of bovine mastitis Streptococcus dysgalactiae 2023 is reported for the first time. The synthesis was accomplished utilizing a stereoselective and convergent [2 + 2] glycosylation strategy inclusive of a disaccharide Schmidt donor and an inclusive rhamnose disaccharide acceptor. The synthetic aminooxy tetrasaccharide was conjugated to T-cell stimulating immunogen PS A1 from Bacteroides fragilis ATCC 25285/NCTC 9343 via a physiologically stable oxime linkage to furnish the first semisynthetic bacterial-based immunogen construct targeting S...
June 3, 2016: Journal of Organic Chemistry
Kevin R Trabbic, Jean-Paul Bourgault, Mengchao Shi, Matthew Clark, Peter R Andreana
PS B, a naturally occurring CD4(+) T-cell simulating zwitterionic polysaccharide from Bacteroides fragilis ATCC 25285/NCTC 9343, was conjugated with aminooxy Thomsen Friedenreich (TF or T) [α-d-Gal-(1,3)-β-d-GalNAc-ONH2] tumor antigen. Immunization in Jax C57BL/6, followed by ELISA revealed IgM and IgG antibody TF specificity. FACS data noted preferential binding to TF-laced MCF-7 cells but not to HCT-116 cells.
April 7, 2016: Organic & Biomolecular Chemistry
Alice Ngo, Kai T Fong, Daniel L Cox, Xi Chen, Andrew J Fisher
Uridine 5'-diphosphate-N-acetylglucosamine (UDP-GlcNAc) acyltransferase (LpxA) catalyzes a reversible reaction for adding an O-acyl group to the GlcNAc in UDP-GlcNAc in the first step of lipid A biosynthesis. Lipid A constitutes a major component of lipopolysaccharides, also referred to as endotoxins, which form the outer monolayer of the outer membrane of Gram-negative bacteria. Ligand-free and UDP-GlcNAc-bound crystal structures of LpxA from Bacteroides fragilis NCTC 9343, the most common pathogenic bacteria found in abdominal abscesses, have been determined and are presented here...
May 2015: Acta Crystallographica. Section D, Biological Crystallography
Marlena M Wilson, D Eric Anderson, Harris D Bernstein
Bacteroides fragilis is a widely distributed member of the human gut microbiome and an opportunistic pathogen. Cell surface molecules produced by this organism likely play important roles in colonization, communication with other microbes, and pathogenicity, but the protein composition of the outer membrane (OM) and the mechanisms used to transport polypeptides into the extracellular space are poorly characterized. Here we used LC-MS/MS to analyze the OM proteome and secretome of B. fragilis NCTC 9343 grown under laboratory conditions...
2015: PloS One
Kevin R Trabbic, Ravindra A De Silva, Peter R Andreana
The zwitterionic polysaccharide PS A1 from anaerobe Bacteroides fragilis ATCC 25285/NCTC 9343 is known to elicit a T-cell-dependent, major histocompatibility complex class II (MHCII) immune response through a correspondingly similar protein-antigen-based mechanism/pathway. The biological activity of PS A1 is known to arise from alternating charged motifs on adjacent monosaccharides comprising a tetrameric repeating oligomeric unit creating an alpha-helical secondary structure. However, we have learned that this alpha-helical structural characteristic may not play a role in immune activation...
August 1, 2014: MedChemComm
Bruna P G V Galvão, Brandon W Weber, Mohamed S Rafudeen, Eliane O Ferreira, Sheila Patrick, Valerie R Abratt
Bacteroides fragilis is an opportunistic pathogen which can cause life threatening infections in humans and animals. The ability to adhere to components of the extracellular matrix, including collagen, is related to bacterial host colonisation. Collagen Far Western analysis of the B. fragilis outer membrane protein (OMP) fraction revealed the presence two collagen adhesin bands of ∼ 31 and ∼ 34 kDa. The collagen adhesins in the OMP fraction were separated and isolated by two-dimensional SDS-PAGE and also purified by collagen affinity chromatography...
2014: PloS One
Kai Chen, Marcel Reuter, Bansi Sanghvi, Gareth A Roberts, Laurie P Cooper, Matthew Tilling, Garry W Blakely, David T F Dryden
Anti-restriction and anti-modification (anti-RM) is the ability to prevent cleavage by DNA restriction-modification (RM) systems of foreign DNA entering a new bacterial host. The evolutionary consequence of anti-RM is the enhanced dissemination of mobile genetic elements. Homologues of ArdA anti-RM proteins are encoded by genes present in many mobile genetic elements such as conjugative plasmids and transposons within bacterial genomes. The ArdA proteins cause anti-RM by mimicking the DNA structure bound by Type I RM enzymes...
March 2014: Biochimica et Biophysica Acta
Kazuki Kawaguchi, Takeshi Senoura, Shigeaki Ito, Toki Taira, Hiroyuki Ito, Jun Wasaki, Susumu Ito
We have proposed a new mannan catabolic pathway in Bacteroides fragilis NCTC 9343 that involves a putative mannanase ManA in glycoside hydrolase family 26 (BF0771), a mannobiose and/or sugar transporter (BF0773), mannobiose 2-epimerase (BF0774), and mannosylglucose phosphorylase (BF0772). If this hypothesis is correct, ManA has to generate mannobiose from mannans as the major end product. In this study, the BF0771 gene from the B. fragilis genome was cloned and expressed in Escherichia coli cells. The expressed protein was found to produce mannobiose exclusively from mannans and initially from manno-oligosaccharides...
January 2014: Archives of Microbiology
Laura C Wieland Brown, Cristina Penaranda, Purna C Kashyap, Brianna B Williams, Jon Clardy, Mitchell Kronenberg, Justin L Sonnenburg, Laurie E Comstock, Jeffrey A Bluestone, Michael A Fischbach
While the human gut microbiota are suspected to produce diffusible small molecules that modulate host signaling pathways, few of these molecules have been identified. Species of Bacteroides and their relatives, which often comprise >50% of the gut community, are unusual among bacteria in that their membrane is rich in sphingolipids, a class of signaling molecules that play a key role in inducing apoptosis and modulating the host immune response. Although known for more than three decades, the full repertoire of Bacteroides sphingolipids has not been defined...
July 2013: PLoS Biology
Masahito Hashimoto, Haruka Eguchi, Kazuki Tawaratsumida, Teruo Kirikae, Yasuo Suda
Bacteroides fragilis is found among the normal intestinal flora and is involved in host immunostimulation via TLR2. Its cell surface components, such as LPS and capsular polysaccharides, were reported to participate in host immunostimulation. In this study, we report on the existence of a lipoprotein that acts as a TLR2 stimulant in B. fragilis. The TLR2-stimulating lipoprotein was obtained using Triton X-114-water phase partitioning followed by preparative SDS-PAGE. Its N-terminal hydrophobic peptide, which was separated from a tryptic digest, was characterized as a triacylated lipopeptide, and the lipoprotein was identified as BF1333 by mass spectrometry of Asp-N-digested peptides...
2013: Innate Immunity
Ravindra A De Silva, Dananjaya K Appulage, Halina Pietraszkiewicz, Kevin R Bobbitt, Joe Media, JiaJiu Shaw, Fred A Valeriote, Peter R Andreana
The tumor-associated carbohydrate antigen/hapten Thomsen-nouveau (Tn; a-D-GalpNAc-ONH2) was conjugated to a zwitterionic capsular polysaccharide, PS A1, from commensal anaerobe Bacteroides fragilis ATCC 25285/NCTC 9343 for the development of an entirely carbohydrate cancer vaccine construct and probed for immunogenicity. This communication discloses that murine anti-Tn IgG3 antibodies both bind to and recognize human tumor cells that display the Tn hapten. Furthermore, the sera from immunization of mice with Tn-PS A1 contain cytokine interleukin 17 (IL-17A), which is known to possess anti-tumor function and represents a striking difference to an IL-2, and IL-6 profile obtained with anti-PS A1 sera...
April 2012: Cancer Immunology, Immunotherapy: CII
Michael J Coyne, C Mark Fletcher, Barbara Reinap, Laurie E Comstock
Xylose is rarely described as a component of bacterial glycans. UDP-xylose is the nucleotide-activated form necessary for incorporation of xylose into glycans and is synthesized by the decarboxylation of UDP-glucuronic acid (UDP-GlcA). Enzymes with UDP-GlcA decarboxylase activity include those that lead to the formation of UDP-xylose as the end product (Uxs type) and those synthesizing UDP-xylose as an intermediate (ArnA and RsU4kpxs types). In this report, we identify and confirm the activities of two Uxs-type UDP-GlcA decarboxylases of Bacteroides fragilis, designated BfUxs1 and BfUxs2...
October 2011: Journal of Bacteriology
Elisabeth Nagy, Simone Becker, József Sóki, Edit Urbán, Markus Kostrzewa
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is increasingly used in clinical microbiological laboratories to identify bacteria and fungi at a species level and to subtype them. The cfiA gene encoding the unique carbapenemases found in Bacteroides is restricted to division II Bacteroides fragilis strains. The aim of this study was to evaluate whether MALDI-TOF MS is suitable for differentiating B. fragilis strains which harbour the cfiA gene from those that do not...
November 2011: Journal of Medical Microbiology
Takeshi Senoura, Shigeaki Ito, Hidenori Taguchi, Mariko Higa, Shigeki Hamada, Hirokazu Matsui, Tadahiro Ozawa, Shigeki Jin, Jun Watanabe, Jun Wasaki, Susumu Ito
The consecutive genes BF0771-BF0774 in the genome of Bacteroides fragilis NCTC 9343 were found to constitute an operon. The functional analysis of BF0772 showed that the gene encoded a novel enzyme, mannosylglucose phosphorylase that catalyzes the reaction, 4-O-β-d-mannopyranosyl-d-glucose+Pi→mannose-1-phosphate+glucose. Here we propose a new mannan catabolic pathway in the anaerobe, which involves 1,4-β-mannanase (BF0771), a mannobiose and/or sugar transporter (BF0773), mannobiose 2-epimerase (BF0774), and mannosylglucose phosphorylase (BF0772), finally progressing to glycolysis...
May 20, 2011: Biochemical and Biophysical Research Communications
Sheila Patrick, Garry W Blakely, Simon Houston, Jane Moore, Valerie R Abratt, Marcelo Bertalan, Ana M Cerdeño-Tárraga, Michael A Quail, Nicola Corton, Craig Corton, Alexandra Bignell, Andrew Barron, Louise Clark, Stephen D Bentley, Julian Parkhill
Comparison of the complete genome sequence of Bacteroides fragilis 638R, originally isolated in the USA, was made with two previously sequenced strains isolated in the UK (NCTC 9343) and Japan (YCH46). The presence of 10 loci containing genes associated with polysaccharide (PS) biosynthesis, each including a putative Wzx flippase and Wzy polymerase, was confirmed in all three strains, despite a lack of cross-reactivity between NCTC 9343 and 638R surface PS-specific antibodies by immunolabelling and microscopy...
November 2010: Microbiology
Sheila Patrick, Simon Houston, Zubin Thacker, Garry W Blakely
The obligate anaerobe Bacteroides fragilis is a normal resident of the human gastrointestinal tract. The clinically derived B. fragilis strain NCTC 9343 produces an extensive array of extracellular polysaccharides (EPS), including antigenically distinct large, small and micro- capsules. The genome of NCTC 9343 encodes multiple gene clusters potentially involved in the biosynthesis of EPS, eight of which are implicated in production of the antigenically variable micro-capsule. We have developed a rapid and robust method for generating marked and markerless deletions, together with efficient electroporation using unmodified plasmid DNA to enable complementation of mutations...
April 2009: Microbiology
Takeshi Senoura, Hidenori Taguchi, Shigeaki Ito, Shigeki Hamada, Hirokazu Matsui, Satoru Fukiya, Atsushi Yokota, Jun Watanabe, Jun Wasaki, Susumu Ito
Cellobiose 2-epimerase (CE, EC catalyzes the reversible epimerization of cellobiose to 4-O-beta-D-glucopyranosyl-D-mannose. In this study, we found a CE gene in the genome sequence of non-cellulolytic Bacteroides fragilis NCTC 9343. The recombinant enzyme, expressed in Escherichia coli cells, catalyzed a hydroxyl stereoisomerism at the C-2 positions of the reducing terminal glucose and at the mannose moiety of cello-oligosaccharides, lactose, beta-mannobiose (4-O-beta-D-mannopyranosyl-D-mannose), and globotriose [O-alpha-D-galactopyranosyl-(1-->4)-O-beta-D-galactopyranosyl-(1-->4)-D-glucose]...
February 2009: Bioscience, Biotechnology, and Biochemistry
L Pumbwe, D W Wareham, J Aduse-Opoku, J S Brazier, H M Wexler
This study investigated the mechanisms of multidrug resistance (MDR) in an isolate of Bacteroides fragilis (WI1) from a patient with anaerobic sepsis. The MDR of WI1 affected susceptibility to beta-lactams, clindamycin, fluoroquinolones, metronidazole and tetracycline. In addition to its 5.31-Mb chromosome, WI1 possessed two low-copy-number plasmids, pHagl (5.6 kb) and pHag2 (9.9 kb), that were absent from B. fragilis NCTC 9343. Restriction digestion with EcoRV, HindIII and SstI, combined with DNA sequencing, revealed that pHAG2 contained a tet(Q) gene at base position 3689 that resided on the conjugative transposon CTn341...
February 2007: Clinical Microbiology and Infection
Simy L Buckwold, Nadja B Shoemaker, Cynthia L Sears, Augusto A Franco
The related genetic elements flanking the Bacteroides fragilis pathogenicity island (PAI) in enterotoxigenic B. fragilis (ETBF) 86-5443-2-2 and also present in pattern III nontoxigenic B. fragilis (NTBF) NCTC 9343 were defined as putative conjugative transposons (CTns), designated CTn86 and CTn9343, respectively (A. A. Franco, J. Bacteriol. 181:6623-6633, 2004). CTn86 and CTn9343 have the same basic structures except that their encoded transposases have low similarity and CTn9343 lacks the B. fragilis PAI and contains an extra 7-kb region not present in CTn86...
January 2007: Applied and Environmental Microbiology
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