Project description:The global transcriptome of the Bifidobacterium animalis subsp. lactis Bl-04 was analyzed during exponential growth on 11 prebiotic carbohydrates and glucose to identify the specific gene cluster differentially upregulated in response to each carbohydrate.
Project description:The global transcriptome of the Bifidobacterium animalis subsp. lactis Bl-04 was analyzed during exponential growth on 11 prebiotic carbohydrates and glucose to identify the specific gene cluster differentially upregulated in response to each carbohydrate. Affymetrix hybridization experiments were performed to compare the differential transcriptional profiles of the B. lactis Bl-04 at the early-log (OD600nm 0.3-0.5) phase. 12 carbohydrates were tested with two technical replicates to each condition for a total of 24 hybridizations.
Project description:Although intestinal microbiota play a pivotal role in the development of host immune system this biological issue was not so far studied in great detail. In this study we examined immune response of Caco-2 enterocytes after incubation with common probiotic Bifidobacterium animalis subsp. lactis BB-12 for 4 hours. We used microarrays to inspect the global gene expression of Caco-2 cells upon co-culturing with B. animalis subsp. lactis BB-12 and several distinct immune-related genes up-regulated during this process.
Project description:Commercial probiotic bacteria must be tested for acquired antibiotic resistance elements to avoid potential transfer to pathogens. The European Food Safety Authority recommends testing resistance using microdilution culture techniques previously used to establish inhibitory thresholds for the Bifidobacterium genus. Many Bifidobacterium animalis subsp. lactis strains exhibit increased resistance to tetracycline, historically attributed to the ribosomal protection gene tet(W). However, some strains that harbor genetically identical tet(W) genes show various inhibition levels suggesting that other genetic elements also contribute to observed differences. Here, we adapted several molecular assays to confirm the inhibition of B. animalis subsp. lactis strains Bl-04 and HN019, and employed RNA-seq to assess the transcriptional differences related to genomic polymorphisms. We detected specific stress responses to the antibiotic by correlating ATP concentration to viable genome copies from droplet digital PCR, and found that the bacteria were still metabolically active in high drug concentrations. Transcriptional analyses revealed that several polymorphic regions, particularly a novel multi-drug efflux transporter, were differentially expressed between the strains in each experimental condition, likely having phenotypic effects. We also found that the tet(W) gene was up-regulated only during sub-inhibitory tetracycline concentrations, while two novel tetracycline resistance genes were up-regulated at high concentrations. Furthermore, many genes involved in amino acid metabolism and transporter function were up-regulated while genes for complex carbohydrate utilization, protein metabolism, and CRISPR-Cas systems were down-regulated. These results provide high-throughput means for assessing antibiotic resistance and determine the genetic network that contributes to the global tetracycline response between two highly related probiotic strains.
Project description:Although intestinal microbiota play a pivotal role in the development of host immune system this biological issue was not so far studied in great detail. In this study we examined immune response of Caco-2 enterocytes after incubation with common probiotic Bifidobacterium animalis subsp. lactis BB-12 for 4 hours. We used microarrays to inspect the global gene expression of Caco-2 cells upon co-culturing with B. animalis subsp. lactis BB-12 and several distinct immune-related genes up-regulated during this process. One time point (T4) and two controls (T0) were analysed. T0 represent differentiated Caco-2 cells cultivated for 3 weeks. T4 represents differentiated Caco-2 cells cultivated for 3 weeks plus consequent 4 hours of co-cultivation with B. animalis subsp. lactis BB-12. 3 technical replicates for T0-1, T0-2 or T4 were pooled to a single sample, RNA extracted and further used in gene expression experiments.
Project description:Comparison of the growth of Bifidobacterium animalis subsp. lactis BB12 in MRS (without carbon source) with either 2% XOS (xylo-oligosaccharides) or 2% glucose using whole-genome transcriptome analysis.
Project description:Modulation of gut microbiota through probiotic supplementation is an interesting strategy to prevent obesity We use microarrays to study the global genome expression of C. elegans fed with the probiotic strain Bifidobacterium animalis sbsp. lactis CECT 8145
Project description:Modulation of gut microbiota through probiotic supplementation is an interesting strategy to prevent obesity We use microarrays to study the global genome expression of C. elegans fed with the probiotic strain Bifidobacterium animalis sbsp. lactis CECT 8145 Wild type strain N2 of C. elegans was cutured in Nematode Growth medium (NGM, control fed) or NGM with a bacterial lawn fed of the strain B. animalis subsp. lactis CECT 8145, until reach young adult stage. Worm population were age-synchronized. RNA was isolated from each populations (control and treated) using RNAasy Kit (Qiagen) and hybridizated on Affymetrix microarrays.
