Project description:Enterococcus faecalis is a common commensal organism and a prolific nosocomial pathogen that causes biofilm-associated infections. Numerous E. faecalis OG1RF genes required for biofilm formation have been identified, but few studies have compared genetic determinants of biofilm formation and biofilm morphology across multiple conditions. Here, we cultured transposon (Tn) libraries in CDC biofilm reactors in two different media and used Tn sequencing (TnSeq) to identify core and accessory biofilm determinants, including many genes that are poorly characterized or annotated as hypothetical. Multiple secondary assays (96-well plates, submerged Aclar, and MultiRep biofilm reactors) were used to validate phenotypes of new biofilm determinants.
Project description:Liquid cultures of Enterococcus faecalis OG1RF and OG1RF Δbph were grown in tryptic soy broth without added dextrose (TSB-D) for 2 and 4 hr. At each time point, the transcriptomes were compared to identify differentially expressed genes in the Δbph mutant.
Project description:The goal of this study was to determine how the method of pooling (combining mutants) for bacteral Tn libraries affected mutant distribution. Previously we generated a pooled version of a~6,800 Tn mutant library in Enterococcus faecalis OG1RF by plating and scraping individual mutants. Here, we combined liquid cultures grown in deep well plates. DNA from the new pooled library was extracted, and TnSeq was used to compare mutant distribution between the old (plate scraping) and new (liquid pooling) Tn library formats. This is important because it will guide best practices for handling large collections of bacterial mutants.
Project description:Transcriptional profiling to define the stringent response regulon and significance of basal (p)ppGpp levels in E. faecalis OG1RF. RNA was extracted from four replicate samples of each strain of interest and labeled with Cy3. For each replicate, labeled RNA was hybridized to slides along with Cy5-labeled reference RNA, extracted from E. faecalis OG1RF cells grown to mid-log.
Project description:Changes in Enterococcus faecalis OG1RF gene expression during infection in a rabbit model of subdermal abscess formation were studied using microarray analysis.
Project description:Changes in Enterococcus faecalis OG1RF(pCF10) gene expression at 4 hours post-infection in a rabbit model of subdermal abscess formation were studied using RNA-seq analysis.