ABSTRACT: Transcriptional profiling of Bifidobacterium longum mutant versus wt strain in exponentional phase Keywords: Characterization of natural mutant
Project description:Transcriptional profiling of Bifidobacterium longum mutant versus wt strain in exponentional phase Keywords: Characterization of natural mutant One B. longum mutant (HPR2) was analysed versus the wt strain NCC2705 in: exponential phase 37°,pH 6.0, MRS, headspace flushing with CO2. Three biological replicates.
Project description:Transcriptional profiling of Bifidobacterium longum mutants versus wt strain in exponentional phase, with or without heat-shock treatment, and in stationary phase Keywords: Characterization of natural mutants
Project description:Transcriptional profiling of Bifidobacterium longum mutants versus wt strain in exponentional phase, with or without heat-shock treatment, and in stationary phase Keywords: Characterization of natural mutants Two B. longum mutants (NCC2912 and NCC2913) were analysed versus the wt strain NCC2705 in three conditions : exponential phase 37°, exponential phase with 7 min 50° heat shock, stationary phase. Two biologic replicates and 2 technical replicates
Project description:The purpose of this project was to determine the whole transcriptome response of Bifidobacterium longum subsp. longum SC596 to pooled and individual human milk oligosaccharides (HMO) relative to lactose
Project description:Bifidobacterium longum subsp. infantis is a bacterial commensal that colonizes the breast-fed infant gut where it utilizes indigestible components delivered in human milk. Accordingly, human milk contains several non-protein nitrogenous molecules, including urea at high abundance. This project investigates the degree to which urea is utilized as a primary nitrogen source by Bifidobacterium longum subsp. infantis and incorporation of hydrolysis products into the expressed proteome.
Project description:A continuous culture of Bifidobacterium longum NCC2705 was carried out in a 2.5-l reactor (Bioengineering AG, Wald, Switzerland), equipped with a Biospectra control system (Biospectra AG, Schlieren, Switzerland) and containing 2 l of MRS, added of 0.05% cysteine, inoculated with 2 % (v/v) preculture. The temperature was maintained at 37°C and the pH at 6.0 by addition of 5 M NaOH. The culture was stirred constantly at 250 rpm using two rushton type propellers. Anaerobic conditions were maintained by flushing the headspace of the reactor with CO2. After 8 h in batch mode the culture was run in continuous mode at a dilution rate of 0.1 h-1. Fresh medium was added using a peristaltic pump (Alitea, Bioengineering AG, Wald, Switzerland), and fermented broth harvested with a second peristaltic pump (Alitea, Bioengineering AG, Wald, Switzerland) set at a slightly higher flow rate. A stabilization period of 90 h (corresponding to nine reactor volume changes) was operated prior culture monitoring (t=0). Aliquots of 2 ml taken at t=31, 134 and 211 h were centrifuged (4,000 g, 1 min, room temperature) for transcriptomic analysis. Supernatants were discarded and cell pellets snap frozen in liquid nitrogen and stored at -80ºC until RNA-extraction. Keywords: Time course of Bifidobacterium longum in continuous culture Bifidobacterium longum NCC2705 at time 31 versus time 134 h and versus time 211 h in continuous culture. Two technical replicares with dyes swaps
Project description:To study the differentiation of Bifidobacterium longum-specific T cells, we stimulated neonatal or naive adult T cells with B. longum-pulsed monocytes and compared them to resting cells from the same donor.
Project description:The purpose of this project was to determine the whole transcriptome response of Bifidobacterium longum subsp. infantis to human milk urea compared to complex nitrogen and L-cysteine.
Project description:Although oral administration of Bifidobacterium longum (B. longum) relieves irritable bowel syndrome (IBS) symptoms in a clinical setting, the underlying mechanisms remain undetermined. Herein, we confirmed that B. longum ameliorated defecation habits and alleviated visceral hypersensitivity in water avoidance stress (WAS) rats. Further analysis revealed that B. longum enhanced mucosal repair, promoted the production of lysozyme, and ameliorated microbiota dysbiosis in WAS rats. These activities are all closely correlated with Paneth cell function. In vitro, we incubated primary cultured enteroids with B. longum and found that this bacterium promoted the proliferation of these organoids, which may be attributed to the up-regulated expression of the stem niche factors WNT3A and TGF-β which are serected by the Paneth cells. On the basis of our findings, we propose that B. longum relieves IBS by restoring the antimicrobial activity and stem niche maintenance functions of Paneth cells.