Project description:Hundreds of microbial species were found to be transcriptionally active in the human gut microbiome based on the expression profiling of ca. 680.000 microbial genes
Project description:"Omics" technologies have been developed to understand the whole complex microbial systems; however, most omics studies reported so far were utilized to analyze the living matters of “single-species”. To understand the cell-cell interaction in the gut microbial complex, we selected to examine the interaction of Escherichia coli O157:H7 (O157) and Bifidobacterium longum (BL), known as a pathogenic and a commensal bacteria, as a first step for understanding the whole gut microbial complex. We have developed a novel time-lapse 2D-NMR metabolic profiling system in order to measure the extracellular metabolites, which are considered a key factor to understand the bacterial crosstalk. Furthermore, in combination with transcriptome and proteome analysis, we found that the relationship between BL and O157 could be partially regarded as the producer and the consumer of nutrients, especially in the case of serine and aspartate metabolism. These findings suggest that our novel profiling systems could be a powerful tool toward understanding crosstalk of the whole microbial complex such as the gut, industrial bioreactors or environmental microbial communities. In vitro mono and coculture were performed. All experiments were performed in duplicate.
Project description:The indigenous human gut microbiota is a major contributor to the human superorganism with established roles in modulating nutritional status, immunity, and systemic health including diabetes and obesity. The complexity of the gut microbiota consisting of over 1012 residents and approximately 1000 species has thus far eluded systematic analyses of the precise effects of individual microbial residents on human health. In contrast, health benefits have been shown upon ingestion of certain so-called probiotic Lactobacillus strains in food products and nutritional supplements, thereby providing a unique opportunity to study the global responses of a gut-adapted microorganism in the human gut and to identify the molecular mechanisms underlying microbial modulation of intestinal physiology, which might involve alterations in the intestinal physico-chemical environment, modifications in the gut microbiota, and/or direct interaction with mucosal epithelia and immune cells. Here we show by transcriptome analysis using DNA microarrays that the established probiotic bacterium, L. plantarum 299v, adapts its metabolic capacity in the human digestive tract for carbohydrate acquisition and expression of exo-polysaccharide and proteinaceous cell surface compounds. This report constitutes the first application of global gene expression profiling of a gut-adapted commensal microorganism in the human gut. Comparisons of the transcript profiles to those obtained for L. plantarum WCFS1 in germ-free mice revealed conserved L. plantarum responses indicative of a core transcriptome expressed in the mammalian gut and provide new molecular targets for determining microbial-host interactions affecting human health. Hybridization of the samples against a common reference of gDNA isolated from L. plantarum 299v
Project description:The interrelationships between our diets and the structure and operations of our gut microbial communities are poorly understood. A model microbial community of ten sequenced human gut bacteria was introduced into gnotobiotic mice and changes in the abundance of each species were measured in response to randomized perturbations of four defined ingredients in the host diet. From the responses, we developed a statistical model that predicted over 50% of the variation in species abundance in response to the diet perturbations and were able to identify which factors in the diet best explained the changes seen for each community member. The community’s transcriptional response was driven by the absolute abundance of each species, as diet ingredient concentrations were not associated with significant changes in the transcription of individual community members.
Project description:Hundreds of microbial species were found to be transcriptionally active in the human gut microbiome based on the expression profiling of ca. 680.000 microbial genes As a part of the MetaHIT cohort 233 human stool samples were transcriptionally profiled using a custom made microarray that included probes for most prevalent microbial genes in the cohort as established by whole-genome sequencing of the same samples
Project description:The proteomes of three amphipod species, a Holarctic species Gammarus lacustris and two Biakal species Eulimnogammarus verrucosus and Eulimnogammarus cyaneus, were received by LC-MS/MS with TMT-labeling. All animals were collected in August 2018. Before the exposition, animals were acclimated in 6C for 25 days. Three species of amphipods were exposed to heat stress (24.6 C for 24 h) and control temperature (6C for 24 h).
Project description:"Omics" technologies have been developed to understand the whole complex microbial systems; however, most omics studies reported so far were utilized to analyze the living matters of “single-species”. To understand the cell-cell interaction in the gut microbial complex, we selected to examine the interaction of Escherichia coli O157:H7 (O157) and Bifidobacterium longum (BL), known as a pathogenic and a commensal bacteria, as a first step for understanding the whole gut microbial complex. We have developed a novel time-lapse 2D-NMR metabolic profiling system in order to measure the extracellular metabolites, which are considered a key factor to understand the bacterial crosstalk. Furthermore, in combination with transcriptome and proteome analysis, we found that the relationship between BL and O157 could be partially regarded as the producer and the consumer of nutrients, especially in the case of serine and aspartate metabolism. These findings suggest that our novel profiling systems could be a powerful tool toward understanding crosstalk of the whole microbial complex such as the gut, industrial bioreactors or environmental microbial communities.
Project description:The impacts of individual commensal microbes on immunity and disease can differ dramatically depending on the surrounding microbial context, yet the specific bacterial combinations that dictate divergent immunological outcomes in humans remain largely undefined. We isolated a novel Allobaculum strain from an inflammatory bowel disease (IBD) patient that elicited antigen-specific mucosal and systemic antibody responses at homeostasis and exacerbated colitis in gnotobiotic mice. Using human microbiota-associated mouse models, we uncovered an inverse correlation between Allobaculum and the taxonomically-divergent immunostimulatory species Akkermansia muciniphila, which was also reflected in human cohorts. Co-colonization with Allobaculum and A. muciniphila reprogrammed the immune responses evoked by each microbe on its own, ameliorated Allobaculum-induced colitis, and blunted A. muciniphila-induced T and B cell responses. These studies thus identify a reciprocal ‘epistatic’ interaction between unique immunostimulatory human gut bacteria and establish a generalizable framework to dissect the role of microbial context in strain-specific microbial effects on human disease.
Project description:Here, we report analysis of both the bacterial and host transcriptome as affected by colonization of R. hominis in the mouse gut. Microbial genes required for colonization and adaptation in the murine gut, as well as host genes responding to colonization by this bacterial species, were uncovered.