Project description:Rag1-/- C57BL/6 or Rag1-/- C57BL/6 injected with the IgA producing hybridoma producing 225.4 anti- Bacteroides thetaiotaomicron (Capsular polysaccharide 4 dependent carbohydrate epitope specific epitope) mice were colonized with B. thetaiotaomicron wildtype strain VPI-5482 for 10 days. Cecal bacteria were harvested and snap frozen and RNA isolated. Keywords: Single time point, experimental and control groups.
Project description:Analysis of the Bacteroides thetaiotaomicron(BT) transcriptome during co-culture with Caco-2 intestinal epithelial cells To identify potential bacterial protein(s) involved in the anti-inflammatory effect of BT in colitis, BT was incubated with Caco-2 human intestinal epithelial cells for 2 hours, and bacterial gene expression was assessed on a Bacteroides thetaiotaomicron VPI-5482 specific microarray. Forty-three BT genes were up-regulated by five-fold or more and of these, twenty genes encoded hypothetical proteins.
Project description:Comparisons of gnotobiotic Rag1-/- mice, with and without subcutaneous 260.8 hybridomas, disclosed that this IgA does not affect B. thetaiotaomicron population density or suppress 260.8 epitope production but does affect bacterial gene expression in ways that are emblematic of a diminished host innate immune response. C57BL/6 wildtype, C57BL/6J Rag1-/- , and C57BL/6J Rag1-/- mice harboring the 260.8 IgA producing hybridoma were colonized for 10 days with Bacteroides thetaiotaomicron VPI-5482.
Project description:We used Affymetrix GeneChips to determine the physiological differences between biofilm and planktonic cells of Bacteroides thetaiotaomicron strain VPI-5482 (ATCC 29148) by comparing gene expression. For this purpose, B. thetaiotaomicron cells were grown in sterile, continuous flow bioreactors fed with tryptone, yeast extract, glucose (TYG) medium. The bioreactors were controlled at a temperature of 37C using a water jacket and a recirculating water heater. After 8 hours post-inoculation, planktonic cells were harvested from the bulk solution in the bioreactor, and after 8 days post-inoculation, the biofilm was scraped from the carbon paper. RNA was harvested from both biofilm and planktonic populations. RNA was extracted by a phenol:chloroform method and purified with a Qiagen RNA Easy mini-kit. Overall growth conditions are summarized above. The experimental conditions were: biofilm (BF), and planktonic (PL).
Project description:We used Affymetrix GeneChips to determine the physiological differences between biofilm and planktonic cells of Bacteroides thetaiotaomicron strain VPI-5482 (ATCC 29148) by comparing gene expression. For this purpose, B. thetaiotaomicron cells were grown in sterile, continuous flow bioreactors fed with tryptone, yeast extract, glucose (TYG) medium. The bioreactors were controlled at a temperature of 37C using a water jacket and a recirculating water heater. After 8 hours post-inoculation, planktonic cells were harvested from the bulk solution in the bioreactor, and after 8 days post-inoculation, the biofilm was scraped from the carbon paper. RNA was harvested from both biofilm and planktonic populations. RNA was extracted by a phenol:chloroform method and purified with a Qiagen RNA Easy mini-kit.
Project description:The goal of this project was to sequence the transcriptome of wild type Bacteroides thetaiotaomicron VPI-5482 grown in minimal media with either glucose or bovine alpha 1 acid glycoprotein (AAGP) as the sole carbon source. Using these data we could then compare relative gene expression levels under each condition and identify genes specifically upregulated during growth on AAGP. Analysis of the spent media indicated that only the N-glycan component of the AAGP had been used by the cells to support growth.
Project description:Despite accepted health benefits of dietary fiber, little is known about the mechanisms by which fiber deprivation impacts the gut microbiota and alters disease risk. Using a gnotobiotic model, in which mice were colonized with a synthetic human gut microbiota, we elucidated the functional interactions between dietary fiber, the gut microbiota and the colonic mucus barrier, which serves as a primary defence against pathogens. We show that during chronic or intermittent dietary fiber deficiency, the gut microbiota resorts to host-secreted mucus glycoproteins as a nutrient source, leading to erosion of the colonic mucus barrier. Dietary fiber deprivation promoted greater epithelial access and lethal colitis by the mucosal pathogen, Citrobacter rodentium, but only in the presence of a fiber-deprived microbiota that is pushed to degrade the mucus layer. Our work reveals intricate pathways linking diet, gut microbiome and intestinal barrier dysfunction, which could be exploited to improve health using dietary therapeutics. Germ-free mice (Swiss Webster) were colonized with synthetic human gut microbiota comprising of 14 species belonging to five different phyla (names of bacterial species: Bacteroides thetaiotaomicron, Bacteroides ovatus, Bacteroides caccae, Bacteroides uniformis, Barnesiella intestinihominis, Eubacterium rectale, Marvinbryantia formatexigens, Collinsella aerofaciens, Escherichia coli HS, Clostridium symbiosum, Desulfovibrio piger, Akkermansia muciniphila, Faecalibacterium prausnitzii and Roseburia intestinalis). These mice were fed either a fiber-rich diet or a fiber-free diet for about 6 weeks. The mice were then sacrificed and their cecal tissues were immediately flash frozen for RNA extraction. The extracted RNA was subjected to microarray analysis based on Mouse Gene ST 2.1 strips using the Affy Plus kit. Expression values for each gene were calculated using robust multi-array average (RMA) method.
