Project description:Analysis of changes in gene expression in Enterococcus faecalis OG1 delta-EF2638 mutant compared to wild-type OG1 strain. The deletion mutant has a growth defect when grown with aeration The mutant presented in this study is described and characterized in Vesic, D. and Kristich, C.J. 2012. A Rex-family transcriptional repressor influnces H2O2 accumulation by Enterococcus faecalis. (submitted for publication)
Project description:Gene content in various Enterococcus faecalis strains compared to E. faecalis V583. Strains have been compared to the V583 strain by comparative genomic hybridization using genome-wide PCR-based microarrays representing the V583 genome. Genes have been deemed "present" or "divergent" in the various strains.
Project description:To further investigate the homeostatic response of E. faecalis to Fe exposure, we examine the whole-genome transcriptional response of wild-type (WT) exposed to non toxic Fe excess. This experiment correspond the work titled Transcriptomic response of Enterococcus faecalis to iron excess (work in preparation) A four chip study using total RNA recovered from four separate wild-type cultures of Enterococcus faecalis OG1RF, two controls samples (N medium growth) and two iron samples (N medium gowth with 0.5 mM Fe-NTA). Each chip measures the expression level of 3,114 genome genes from Enterococcus faecalis strain V583 (A7980-00-01).
Project description:Analysis of changes in gene expression in Enterococcus faecalis OG1 delta-EF2638 mutant compared to wild-type OG1 strain. The deletion mutant has a growth defect when grown with aeration The mutant presented in this study is described and characterized in Vesic, D. and Kristich, C.J. 2012. A Rex-family transcriptional repressor influnces H2O2 accumulation by Enterococcus faecalis. (submitted for publication) Microarray analysis was done using RNA isolated from two independent cultures of wild-type Enterococcus faecalis OG1 and two independent cultres of Enterococcus faecalis OG1 delta-EF2638 mutant; each RNA sample was subjected to triplicate hybridization (technical replicates) . Microarrays were custom designed to investigate expression of ORFs in Enterococcus faecalis OG1RF genome. The arrays were designed based on the OG1RF annotation generated with the Rapid Annotation Using Subsystem Technology (RAST) server (Aziz et. al. 2008. BMC Genomics 9:75), as described in Frank et al (2012) Infect. Immun. 80:539. The aim was eighteen probe pairs per ORF, each of which is present in triplicate.
Project description:Enterococcus faecalis is a common gut commensal Gram-positive bacterium that can act as an opportunistic pathogen and is frequently associated with nosocomial and iatrogenic bloodstream infections, such as bacteremia and endocarditis. Bacteria-derived extracellular vesicles (EVs) emerge as key mediators of host-bacteria communication with immunomodulatory roles and mechanistic participation in pathophysiological processes, such as inflammation and infection. However, the functional impact of E. faecalis-derived EVs (Ef-EVs) on host responses and their potential role in shaping host responses during infection remain unclear. In this work, we investigated the immunomodulatory effects of Ef-EVs in vitro on NF-κB/AP-1 reporter cells, primary human monocyte-derived macrophages (HMDMs), human umbilical vein endothelial cells (HUVECs), and macrophages derived from in vivo Ef-EV-treated zebrafish larvae. We found that Ef-EVs can induce pro-inflammatory responses in host macrophages via Toll-like receptor 2 (TLR2) signaling. Using bottom-up assembled bacterial EVs functionalized with the synthetic bacterial ligands as a minimalistic approach to study mechanisms of EV signaling, we demonstrate that Ef-EVs target the plasma membrane TLR2 to induce inflammation in a process uncoupled from their internalization. Furthermore, we found that Ef-EVs induce metabolic reprogramming towards a pro-inflammatory, glycolytic phenotype. Our findings showcase a previously understudied role of Gram-positive EVs in modulating immune signaling and metabolic pathways, advancing our understanding of host-pathogen communication.
