Project description:Functional redundancy in bacterial communities is expected to allow microbial assemblages to survive perturbation by allowing continuity in function despite compositional changes in communities. Recent evidence suggests, however, that microbial communities change both composition and function as a result of disturbance. We present evidence for a third response: resistance. We examined microbial community response to perturbation caused by nutrient enrichment in salt marsh sediments using deep pyrosequencing of 16S rRNA and functional gene microarrays targeting the nirS gene. Composition of the microbial community, as demonstrated by both genes, was unaffected by significant variations in external nutrient supply, despite demonstrable and diverse nutrient–induced changes in many aspects of marsh ecology. The lack of response to external forcing demonstrates a remarkable uncoupling between microbial composition and ecosystem-level biogeochemical processes and suggests that sediment microbial communities are able to resist some forms of perturbation.
Project description:<p>This study involved evaluation of the tissue associated microbiome of the ileal pouch following surgery for ulcerative colitis (UC) or familial adenomatous polyposis (FAP). Individuals were recruited, with biopsies taken from the ileal pouch and the pre-pouch ileum, microbial DNA was extracted and sequenced using 454 pyrosequencing. Total bacterial community structure and abundance were evaluated to determine which changes were characteristic of inflammatory phenotypes including pouchitis (inflammation of the ileal pouch) and a Crohn's disease-like phenotype.</p>
Project description:<p>This study involved evaluation of the tissue associated microbiome of the ileal pouch following surgery for ulcerative colitis (UC) or familial adenomatous polyposis (FAP). Individuals were recruited, with biopsies taken from the ileal pouch and the pre-pouch ileum, microbial DNA was extracted and sequenced using 454 pyrosequencing. Total bacterial community structure and abundance were evaluated to determine which changes were characteristic of inflammatory phenotypes including pouchitis (inflammation of the ileal pouch) and a Crohn's disease-like phenotype.</p>
