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Williams, M. A.

Publications and source records attributed to Williams, M. A..

2 recordsLinked to original sources

Altered Stool Microbiota of Infants with Cystic Fibrosis Shows Reduction in Genera Associated with Immune Programming

Previous work from our group indicated a connection between the gastrointestinal microbiota of infants and children with cystic fibrosis (CF) and airway disease in this population. Here we examine the stool microbiota of infants with CF and from the general population who did not have CF over the first year of life. CF children had reduced gastrointestinal Bacteroides and Bifidobacterium beginning in infancy, even after adjusting for antibiotic treatment. We also identify several metabolic pathways that are enriched or under represented among the microbial communities in the stool of these young patients with CF as compared to children without CF. In vitro studies demonstrated that exposure of the apical face of a polarized Intestinal cell line to Bacteroides thetaiotaomicron significantly reduced production of IL-8 secreted from both the apical and basolateral face of these cells, suggesting a mechanism whereby changes in the intestinal microflora could impact systemic inflammation. This work further establishes a link between gastrointestinal microbiota, systemic inflammation and airway disease, and presents the opportunity for therapeutic probiotic interventions.\n\nSignificance statementThere is a surprising link between gastrointestinal microbial communities and airway disease progression in CF. Here we show that infants with CF [≤]1 year of age show a distinct stool microbiota compared with children of a comparable age from a general population cohort. We detect associations between stool microbes and airway exacerbation events in the cohort of infants with CF, and in vitro studies provide a possible mechanism for this observation. These data argue that current therapeutics do not establish a healthy-like gastrointestinal microbiota in young patients with CF, and we suggest that interventions that direct the gastrointestinal microbiota closer to a healthy state may provide benefit to these patients.

microbiology

COREMIC: a web-tool to search for a root-zone associated CORE MICrobiome

Microbial diversity on earth is extraordinary, and soils alone harbor thousands of species per gram of soil. Understanding how this diversity is sorted and selected into habitat niches is a major focus of ecology and biotechnology, but remains only vaguely understood. A systems-biology approach was used to mine information from databases to show how it can be used to answer questions related to the core microbiome of habitat-microbe relationships. By making use of the burgeoning growth of information from databases, our tool \"COREMIC\" meets a great need in the search for understanding niche partitioning and habitat-function relationships. The work is unique, furthermore, because it provides a user-friendly statistically robust web-tool (http://coremic2.appspot.com), developed using Google App Engine, to help in the process of database mining to identify the \"core microbiome\" associated with a given habitat. A case study is presented using data from 31 switchgrass rhizosphere community habitats across a diverse set of soil and sampling environments. The methodology utilizes an outgroup of 28 non-switchgrass (other grasses and forbs) to identify a core switchgrass microbiome. Even across a diverse set of soils (5 environments), and conservative statistical criteria (presence in more than 90% samples and FDR q-val < 0.05% for Fishers exact test) a core set of bacteria associated with switchgrass was observed. These included, among others, closely related taxa from Lysobacter spp., Mesorhizobium spp, and Chitinophagaceae. These bacteria have been shown to have functions related to the production of bacterial and fungal antibiotics and plant growth promotion. COREMIC can be used as a hypothesis generating or confirmatory tool that shows great potential for identifying taxa that may be important to the functioning of a habitat (e.g. host plant). The case study, in conclusion, shows that COREMIC can identify key habitat-specific microbes across diverse samples, using currently available databases and a unique freely available software.

microbiology