Gut bacteria
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA592411 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Symbiotic bacteria inhabiting the distal human gut have evolved under intense pressure to utilize complex carbohydrates, predominantly plant cell wall glycans abundant in our diets. These substrates are recalcitrant to depolymerization by digestive enzymes encoded in the human genome, but are efficiently targeted by some of the ~103-104 bacterial species that inhabit this niche. These species augment our comparatively narrow carbohydrate digestive capacity by unlocking otherwise unusable sugars and fermenting them into host-absorbable forms, such as short-chain fatty acids. We used phenotype profiling, whole-genome transcriptional analysis and molecular genetic approaches to investigate complex glycan utilization by two fully sequenced and closely related human gut symbionts: Bacteroides thetaiotaomicron and Bacteroides ovatus. Together these species target all of the common glycosidic linkages found in the plant cell wall, as well as host polysaccharides, but each species exhibits a unique ‘glycan niche’: in vitro B. thetaiotaomicron targets plant cell wall pectins in addition to linkages contained in host N- and O-glycans; B. ovatus uniquely targets hemicellulosic polysaccharides along with several pectins, but is deficient in host glycan utilization. Bacteroides ovatus bacteria were grown either in vitro on defined complex glycan sources, or in vivo in the intestinal tract of gnotobiotic mice fed variable diets. Increased in vitro gene expression was used to indicate the genes required for metabolism of complex glycans and compared to in vivo transcriptional activity to determine expression in the mouse gut.
2011-05-01 | E-GEOD-25575 | biostudies-arrayexpress
Project description:Symbiotic bacteria inhabiting the distal human gut have evolved under intense pressure to utilize complex carbohydrates, predominantly plant cell wall glycans abundant in our diets. These substrates are recalcitrant to depolymerization by digestive enzymes encoded in the human genome, but are efficiently targeted by some of the ~103-104 bacterial species that inhabit this niche. These species augment our comparatively narrow carbohydrate digestive capacity by unlocking otherwise unusable sugars and fermenting them into host-absorbable forms, such as short-chain fatty acids. We used phenotype profiling, whole-genome transcriptional analysis and molecular genetic approaches to investigate complex glycan utilization by two fully sequenced and closely related human gut symbionts: Bacteroides thetaiotaomicron and Bacteroides ovatus. Together these species target all of the common glycosidic linkages found in the plant cell wall, as well as host polysaccharides, but each species exhibits a unique ‘glycan niche’: in vitro B. thetaiotaomicron targets plant cell wall pectins in addition to linkages contained in host N- and O-glycans; B. ovatus uniquely targets hemicellulosic polysaccharides along with several pectins, but is deficient in host glycan utilization.
2011-05-01 | GSE25575 | GEO
Project description:Symbiotic bacteria inhabiting the distal human gut have evolved under intense pressure to utilize complex carbohydrates, predominantly plant cell wall glycans abundant in our diets. These substrates are recalcitrant to depolymerization by digestive enzymes encoded in the human genome, but are efficiently targeted by some of the ~103-104 bacterial species that inhabit this niche. These species augment our comparatively narrow carbohydrate digestive capacity by unlocking otherwise unusable sugars and fermenting them into host-absorbable forms, such as short-chain fatty acids. We used phenotype profiling, whole-genome transcriptional analysis and molecular genetic approaches to investigate complex glycan utilization by two fully sequenced and closely related human gut symbionts: Bacteroides thetaiotaomicron and Bacteroides ovatus. Together these species target all of the common glycosidic linkages found in the plant cell wall, as well as host polysaccharides, but each species exhibits a unique ‘glycan niche’: in vitro B. thetaiotaomicron targets plant cell wall pectins in addition to linkages contained in host N- and O-glycans; B. ovatus uniquely targets hemicellulosic polysaccharides along with several pectins, but is deficient in host glycan utilization.
2011-05-01 | GSE25572 | GEO
Project description:Symbiotic bacteria inhabiting the distal human gut have evolved under intense pressure to utilize complex carbohydrates, predominantly plant cell wall glycans abundant in our diets. These substrates are recalcitrant to depolymerization by digestive enzymes encoded in the human genome, but are efficiently targeted by some of the ~103-104 bacterial species that inhabit this niche. These species augment our comparatively narrow carbohydrate digestive capacity by unlocking otherwise unusable sugars and fermenting them into host-absorbable forms, such as short-chain fatty acids. We used phenotype profiling, whole-genome transcriptional analysis and molecular genetic approaches to investigate complex glycan utilization by two fully sequenced and closely related human gut symbionts: Bacteroides thetaiotaomicron and Bacteroides ovatus. Together these species target all of the common glycosidic linkages found in the plant cell wall, as well as host polysaccharides, but each species exhibits a unique ‘glycan niche’: in vitro B. thetaiotaomicron targets plant cell wall pectins in addition to linkages contained in host N- and O-glycans; B. ovatus uniquely targets hemicellulosic polysaccharides along with several pectins, but is deficient in host glycan utilization. Growth of Bacteroides thetaiotaomicron in vitro in minimal medium plus different purified complex glycans. Observation of increased gene expression was used to determine genes that are involved in metabolism of each glycan. Two biological replicates each.
2011-05-01 | E-GEOD-25572 | biostudies-arrayexpress
Project description:This SuperSeries is composed of the following subset Series: GSE25572: Depolymerization of plant cell wall glycans by symbiotic human gut bacteria (Bacteroides thetaiotaomicron) GSE25575: Depolymerization of plant cell wall glycans by symbiotic human gut bacteria (Bacteroides ovatus) Refer to individual Series
2011-05-01 | E-GEOD-25576 | biostudies-arrayexpress
Project description:The gut microbiota promotes immune system development in early life, but the interactions between the gut metabolome and immune cells in the neonatal gut remains largely undefined. Here, we demonstrate that the neonatal gut is uniquely enriched with neurotransmitters, including serotonin; specific gut bacteria produce serotonin directly while downregulating monoamine oxidase A to limit serotonin breakdown. Serotonin directly signals to T cells to increase intracellular indole-3-acetaldehdye to inhibit mTOR activation and thereby promotes the differentiation of regulatory T cells, both ex vivo and in vivo in the neonatal intestine. Oral gavage of serotonin into neonatal mice leads to long-term T cell-mediated antigen-specific immune tolerance towards both dietary antigens and commensal bacteria. Together, our study has uncovered an important role for unique gut bacteria to increase serotonin availability in the neonatal gut and a novel function of gut serotonin to shape T cell response to dietary antigens and commensal bacteria to promote immune tolerance in early life.
2024-01-31 | GSE248692 | GEO
Project description:The gut microbiota promotes immune system development in early life, but the interactions between the gut metabolome and immune cells in the neonatal gut remains largely undefined. Here, we demonstrate that the neonatal gut is uniquely enriched with neurotransmitters, including serotonin; specific gut bacteria produce serotonin directly while downregulating monoamine oxidase A to limit serotonin breakdown. Serotonin directly signals to T cells to increase intracellular indole-3-acetaldehdye to inhibit mTOR activation and thereby promotes the differentiation of regulatory T cells, both ex vivo and in vivo in the neonatal intestine. Oral gavage of serotonin into neonatal mice leads to long-term T cell-mediated antigen-specific immune tolerance towards both dietary antigens and commensal bacteria. Together, our study has uncovered an important role for unique gut bacteria to increase serotonin availability in the neonatal gut and a novel function of gut serotonin to shape T cell response to dietary antigens and commensal bacteria to promote immune tolerance in early life.
2024-01-31 | GSE248691 | GEO
Project description:The gut microbiota promotes immune system development in early life, but the interactions between the gut metabolome and immune cells in the neonatal gut remains largely undefined. Here, we demonstrate that the neonatal gut is uniquely enriched with neurotransmitters, including serotonin; specific gut bacteria produce serotonin directly while downregulating monoamine oxidase A to limit serotonin breakdown. Serotonin directly signals to T cells to increase intracellular indole-3-acetaldehdye to inhibit mTOR activation and thereby promotes the differentiation of regulatory T cells, both ex vivo and in vivo in the neonatal intestine. Oral gavage of serotonin into neonatal mice leads to long-term T cell-mediated antigen-specific immune tolerance towards both dietary antigens and commensal bacteria. Together, our study has uncovered an important role for unique gut bacteria to increase serotonin availability in the neonatal gut and a novel function of gut serotonin to shape T cell response to dietary antigens and commensal bacteria to promote immune tolerance in early life.
2024-01-31 | GSE248690 | GEO
Project description:Background: Probiotic-like bacteria treatment has been described to be associated with gut microbiota modifications. Goal: To decipher if the effects of the tested probiotic-like bacteria are due to the bacteria itself or due to the effects of the bacteria on the gut microbiota. Methodology: In this study, gut microbiota has been analyzed from feces samples of subjects with metabolic syndrome and treated with one of the 2 tested probiotic-like bacteria or with the placebo during 3months.
| EGAS00001003585 | EGA
Project description:Microbiota-induced cytokine responses participate in gut homeostasis, but the cytokine balance at steady-state and the role of individual bacterial species in setting the balance remain elusive. Using gnotobiotic mouse models, we provide a systematic analysis of the role of microbiota in the induction of cytokine responses in the normal intestine. Colonization by a whole mouse microbiota orchestrated a broad spectrum of pro-inflammatory (Th1, Th17) and regulatory T cell responses. Unexpectedly, most tested complex microbiota and individual bacteria failed to efficiently stimulate intestinal cytokine responses. A potent cytokine-inducing function was however associated with non-culturable host-specific species, the prototype of which was the Clostridia-related Segmented Filamentous Bacterium, and this bacterial species recapitulated the coordinated maturation of T cell responses induced by the whole mouse microbiota. Our study demonstrates the non-redundant role of microbiota members in the regulation of gut immune homeostasis.
2009-09-11 | GSE18056 | GEO