Project description:Members of the serpin (serine protease inhibitor) superfamily have been identified in higher, multicellular eukaryotes, as well as in bacteria, although surveillance of available genome sequences indicates that bacterial serpin-encoding (ser) homologs are not widely distributed. In members of the genus Bifidobacterium this gene appears to be present in at least five, and perhaps up to nine, out of 30 species tested. Moreover, phylogenetic analysis using available bacterial and eukaryotic serpin sequences revealed that bifidobacteria specify serpins that form a separate clade. We characterized the ser210B locus of Bifidobacterium breve 210B, which consists of a number of genes, whose deduced protein products display significant similarity to proteins encoded by corresponding loci found in several other bifidobacteria. Northern hybridization, primer extension, micro array analysis, RT-PCR and Quantitative Real Time (qRT) - PCR analysis revealed that a 3.5 kb polycistronic mRNA, encompassing the ser210B operon with a single transcriptional start site, is strongly induced following treatment of B. breve 210B cultures with particular proteases. In contrast, transcription of the ser homolog of other bifidobacteria, such as Bifidobacterium longum subsp. infantis, Bifidobacterium dentium and B. longum subsp. longum, appears to be triggered by a different set of proteases Transcriptional response to protease treatments (kallikrein, papain and chymotrypsin) of Bifidobacterium breve 210B
Project description:Members of the serpin (serine protease inhibitor) superfamily have been identified in higher, multicellular eukaryotes, as well as in bacteria, although surveillance of available genome sequences indicates that bacterial serpin-encoding (ser) homologs are not widely distributed. In members of the genus Bifidobacterium this gene appears to be present in at least five, and perhaps up to nine, out of 30 species tested. Moreover, phylogenetic analysis using available bacterial and eukaryotic serpin sequences revealed that bifidobacteria specify serpins that form a separate clade. We characterized the ser210B locus of Bifidobacterium breve 210B, which consists of a number of genes, whose deduced protein products display significant similarity to proteins encoded by corresponding loci found in several other bifidobacteria. Northern hybridization, primer extension, micro array analysis, RT-PCR and Quantitative Real Time (qRT) - PCR analysis revealed that a 3.5 kb polycistronic mRNA, encompassing the ser210B operon with a single transcriptional start site, is strongly induced following treatment of B. breve 210B cultures with particular proteases. In contrast, transcription of the ser homolog of other bifidobacteria, such as Bifidobacterium longum subsp. infantis, Bifidobacterium dentium and B. longum subsp. longum, appears to be triggered by a different set of proteases
Project description:Human milk oligosaccharides (HMOs) function as prebiotics for beneficial bacteria in the developing gut, often dominated by Bifidobacterium spp. To understand the relationship between Bifidobacterium utilizing HMOs and how the metabolites that are produced could affect the host, we analyzed the metabolism of HMO 2’-fucosyllactose (2’-FL), 3-fucosyllactose (3FL and difucosyllactose (DFL) in Bifidobacterium longum ssp. infantis Bi-26 and ATCC15697. RNA-seq and metabolite analysis was performed on samples at early (A600=0.25), mid-log (0.5-0.7) and late-log phases (1.0-2.0) of growth.
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:Stress survival tactics in bacteria utalize the up- and down-regulation of stress response genes. In bacterial that lack classical stress response genes for oxidative stress, other cellular systems can be used for cell survival. We used custom microarrays to study the regulation of genes in Bifidobacterium longum strains to oxidative stress to elucidate novel stress response mechanisms.
Project description:Untargeted UPLC-MS/MS data from a screen of human gut microbiome commensal isolate bacteria from healthy human donor feces. Isolates include Mediterraneibacter gnavus MSK15.77 (NCBI accession NZ_JAAIRR010000000), Bacteroides ovatus MSK22.29 (NCBI accession NZ_JAHOCX010000000), Bifidobacterium longum DFI.2.45 (NCBI accession NZ_JAJCNS010000000), and Lachnoclostridium scindens SL.1.22 (NCBI accession GCA_020555615.1). The dataset includes validated bile acid standards. All using positive ionization.
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:Extracellular vesicles of the Gram-positive gut symbiont Bifidobacterium longum induce immune-modulatory, anti-inflammatory effects
Project description:Diet-microbe interactions play a crucial role in infant development and modulation of the early-life microbiota. The genus Bifidobacterium dominates the breast-fed infant gut, with strains of B. longum subsp. longum (B. longum) and B. longum subsp. infantis (B. infantis) particularly prevalent within the early-life microbiota. Although, transition from milk to a more diversified diet later in infancy initiates a shift to a more complex microbiome, with concurrent reductions in Bifidobacterium abundance, specific strains of B. longum may persist in individual hosts for prolonged periods of time. Here, we sought to investigate the adaptation of B. longum to the changing infant diet during the early-life developmental window. Genomic characterisation of 75 strains isolated from nine either exclusively breast- or formula-fed infants in the first 18 months of their lives revealed subspecies- and strain-specific intra-individual genomic diversity with respect to glycosyl hydrolase families and enzymes, which corresponded to different dietary stages. Complementary phenotypic growth studies indicated strain-specific differences in human milk oligosaccharide and plant carbohydrate utilisation profiles between and within individual infants, while proteomic profiling identified proteins involved in metabolism of selected carbohydrates. Our results indicate a strong link between infant diet and B. longum subspecies/strain genomic and carbohydrate utilisation diversity, which aligns with a changing nutritional environment i.e. moving from breast milk to a solid food diet. These data provide additional insights into possible mechanisms responsible for the competitive advantage of this bifidobacterial species and their long-term persistence in a single host and may contribute to rational development of new dietary therapies for this important development window.
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.