Bacteria
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA496358 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Distal gut bacteria play a pivotal role in the digestion of dietary polysaccharides by producing a large number of carbohydrate-active enzymes (CAZymes) that the host otherwise does not produce. We report here the design of a high density custom microarray that we used to spot non-redundant DNA probes for more than 6,500 genes encoding glycoside hydrolases and lyases selected from 174 reference genomes from distal gut bacteria. The custom microarray was tested and validated by the hybridization of bacterial DNA extracted from the stool samples of lean, obese and anorexic individuals. Our results suggest that a microarray-based study can detect genes from low-abundance bacteria better than metagenomic-based studies. A striking example was the finding that a gene encoding a GH6-family cellulase was present in all subjects examined, whereas metagenomic studies have consistently failed to detect this gene in both human and animal gut microbiomes. In addition, an examination of eight stool samples allowed the identification of a corresponding CAZome core containing 46 families of glycoside hydrolases and polysaccharide lyases, which suggests the functional stability of the gut microbiota despite large taxonomical variations between individuals. Fecal samples were collected from eight female subjects. Three were obese subjects of BMI kg m-2: 35, 46.8 and 51.3, respectively; age: 42, 21 and 65 years old, respectively. Three were anorexic women of BMI kg m-2: 9.8, 10 and 13.7, respectively; age: 19, 23 and 49 years old, respectively. Finally, two fecal samples from lean women of BMI kg m-2: 18.6 and 23.42 were analyzed.
2013-10-28 | E-GEOD-51760 | biostudies-arrayexpress
Project description:Probiotic bacteria, specific representatives of bacterial species that are a common part of the human microbiota, are proposed to deliver health benefits to the consumer by modulation of intestinal function via largely unknown molecular mechanisms. To explore in vivo mucosal responses of healthy adults to probiotics, we obtained transcriptomes in an intervention study following a double-blind placebo-controlled cross-over design. In the mucosa of the proximal small intestine of healthy volunteers, probiotic strains from the species Lactobacillus acidophilus, L. casei and L. rhamnosus each induced differential gene regulatory networks and pathways in the human mucosa. Comprehensive analyses revealed that these transcriptional networks regulate major basal mucosal processes, and uncovered remarkable similarity to response profiles obtained for specific bioactive molecules and drugs. This study elucidates how intestinal mucosa of healthy humans perceive different probiotics and provides avenues for rationally designed tests of clinical applications. Keywords: mucosal response of healthy adult humans to lactic acid bacteria This study was set up according to a randomised double-blind cross-over placebo-controlled design. It contains transcriptional profiles from biopsies from 7 healthy individuals after oral intake of three different Lactobacillus species or placebo control. In total, this study includes data from 7 individuals x 4 treatments=28 arrays.
2010-09-08 | E-GEOD-18741 | biostudies-arrayexpress
Project description:Some commensal bacteria stimulate the immune system but do not present specific antigenicity. Such adjuvant effects have been reported for the bacterial species Lactobacillus plantarum. To study in vivo human responses to L. plantarum, a randomised double-blind placebo-controlled cross-over study was performed. Healthy adults were provided preparations of living and heat-killed L. plantarum bacteria, biopsies were taken from the intestinal mucosa and altered transcriptional profiles were analysed. Transcriptional profiles of human epithelia displayed striking differences upon exposure to living L. plantarum bacteria harvested at different growth phases. Modulation of NF-κB-dependent pathways was central among the major altered cellular responses. This unique in vivo study shows which cellular pathways are associated with the induction of immune tolerance in mucosal tissues towards common adjuvanticity possessing lactobacilli. Keywords: mucosal response of healthy adult humans to lactic acid bacteria This study was set up according to a randomised double-blind cross-over placebo-controlled design. It contains transcriptional profiles from biopsies from 8 healthy individuals after oral intake of three different growth stages of Lactobacillus plantarum or placebo control. In total, this study includes data from 8 individuals x 4 treatments=32 arrays.
2009-01-20 | E-GEOD-11355 | biostudies-arrayexpress
Project description:Distal gut bacteria play a pivotal role in the digestion of dietary polysaccharides by producing a large number of carbohydrate-active enzymes (CAZymes) that the host otherwise does not produce. We report here the design of a high density custom microarray that we used to spot non-redundant DNA probes for more than 6,500 genes encoding glycoside hydrolases and lyases selected from 174 reference genomes from distal gut bacteria. The custom microarray was tested and validated by the hybridization of bacterial DNA extracted from the stool samples of lean, obese and anorexic individuals. Our results suggest that a microarray-based study can detect genes from low-abundance bacteria better than metagenomic-based studies. A striking example was the finding that a gene encoding a GH6-family cellulase was present in all subjects examined, whereas metagenomic studies have consistently failed to detect this gene in both human and animal gut microbiomes. In addition, an examination of eight stool samples allowed the identification of a corresponding CAZome core containing 46 families of glycoside hydrolases and polysaccharide lyases, which suggests the functional stability of the gut microbiota despite large taxonomical variations between individuals.
2013-10-28 | GSE51760 | GEO
Project description:Flagellins from commensal bacteria can be weak Toll-like receptor (TLR)5 agonists despite high affinity binding to TLR5, ligands we termed “silent flagellins”. To determine if silent flagellins are detectable in the human gut, endogenous flagellins produced by the microbiota were isolated from stool obtained from a healthy adult female donor. TLR5 was used as bait to enrich for silent flagellins and TLR5-bound flagellins were identified by searching peptides against a custom flagellin database built from metagenome sequences.
2022-10-12 | PXD033249 | Pride
Project description:Background:
- Some bacteria found in the large and small intestines help keep people healthy and aid digestion. They may also affect a person s risk of developing cancer. Researchers want to study the relationship between intestinal bacteria and breast cancer risk factors. They can do this by looking at stool and urine samples from postmenopausal women.
Objectives:
- To study intestinal bacteria and its relationship to urine-based markers of breast cancer risk in women.
Eligibility:
- Women between 55 and 69 years of age with a recent mammogram that showed no signs of cancer.
Design:
* Participants will be screened with a medical history and basic health questionnaire.
* At home, participants will complete questionnaires about cancer risk factors and food consumption.
* Participants will also collect urine and stool samples. They will send the samples to the designated labs for study.
* No treatment will be provided as part of this protocol.
| 2114858 | ecrin-mdr-crc
Project description:Intervention1: NIL: NIL
Control Intervention1: NIL: NIL
Primary outcome(s): 1). Comparative difference in gut microbial signatures in healthy individuals, colorectal (CRC) and ulcerative colitis (UC) patients using BugSpeaks microbiome analytical platform
2). Comparative difference in stool metabolites in healthy individuals, CRC and UC patients
Timepoint: Screening Visit (Up to day 3) Baseline Visit- Day 0
| 2721938 | ecrin-mdr-crc
Project description:Small RNA-Seq analysis of on stool samples from an Italian cohort of 120 healthy individuals with three dietary habits. The cohort includes 72 women and 48 men included an equal proportion of vegetarians, vegans and omnivores.
2021-07-30 | GSE171913 | GEO