Project description:Staphylococcus epidermidis is a Gram-positive, coagulase-negative (CoNS) bacterium that is carried asymptomatically on the skin and mucous membranes of virtually all human beings. It is a major cause of nosocomial infections and associated with invasive procedures (Méric et al., 2018). Virulent S. epidermidis strains contaminate indwelling medical devices, such as catheters or implants (Sabaté Brescó et al., 2017), showing pathogenicity traits, e.g., biofilm formation, cell toxicity, or methicillin resistance (Méric et al., 2018). Apart from that, even the low-virulent, low-biofilm forming strain of S. epidermidis ATCC 12228 was shown to form a biofilm under decreased oxygen conditions (Uribe-Alvarez et al., 2015). As a member of the skin and mucosal microbiome, S. epidermidis prevents the colonization of Staphylococcus aureus (Otto, 2011). Its well-studied metabolism and the ability to grow on known media make S. epidermidis a possible reconstruction candidate. A reconstruction of a genome-scale metabolic model (GEM) of S. epidermidis was created using CarveMe (Machado et al., 2018) and carefully refined in subsequent manual curation efforts, using the S. epidermidis ATCC 12228 strain sequence. The model was experimentally validated on multiple media under varying growth conditions, such as different carbon sources.
Project description:Proteomic analysis of a commensal Staphylococcus epidermidis strain in different pH conditions for describing the molecular players involved in the skin-to-blood adaptation of the bacterium.
Project description:Staphylococcus aureus and Staphylococcus epidermidis, two Gram-positive bacteria commonly found in the human skin microbiota, form biofilms that contribute to skin dysbiosis and play a key role in conditions like acne and atopic dermatitis. The Calcitonin Gene-Related Peptide (CGRP) is a human peptide involved in skin inflammation. We previously showed that CGRP enhances the virulence of S. epidermidis MFP04 and that the DnaK chaperone protein is significantly overexpressed in the secretome of CGRP-activated virulent S. epidermidis. In this study, we explored a potential new role of S. epidermidis DnaK in biofilm formation in both S. aureus and S. epidermidis. We showed that recombinant S. epidermidis DnaK differentially affects biofilm formation, whether in two skin commensal staphylococcal strains (S. aureus MFP03 and S. epidermidis MFP04) or in a clinical S. aureus strain (CIP 107093). In the clinical strain S. aureus CIP 107093, biofilm formation was most strongly inhibited. This inhibition involves both the Substrate-Binding Domain and the Nucleotide-Binding Domain of DnaK. Proteomic analysis revealed that DnaK alters the S. aureus biofilm proteome, stabilizing proteins involved in protein degradation like ClpP and ETA, while downregulating key regulatory proteins involved in biofilm development such as SaeS and WalK. These results indicate that S. epidermidis DnaK may contribute to the regulation of S. aureus biofilm formation, suggesting a cross-species regulatory role of DnaK within the skin microbiota.
Project description:We report the application of single cell RNA sequencing technology for high-throughput profiling of nasal microbiome Staphylococcus epidermidis in human nasal epithelial cells.
Project description:We sequenced mRNA from three independent biological replicates of Staphylococcus epidermidis biofilms with different proportion of dormant cells. Whole trancriptome analysis of Staphylococcus epidermidis biofilms with prevented and induced dormancy.
Project description:Staphylococcus aureus Newman and Staphylococcus epidermidis Tu3298, 20 minutes post challenge with sub-inhibitory concentration of sapienic acid vs equivalent concentration of ethanol. Challenge was added at mid logarithmic growth (OD600 0.5). Biological triplicates of samples were sequenced.
Project description:We examined the differential gene expression of Staphylococcus epidermidis and Staphylococcus epidermidis in dual species biofilms. Therefore, we performed RNA-Seq on single and dual species biofilms and we compared the gene expression levels in dual species biofilms to those in single species biofilms.