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: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.
Project description:Bacterial sepsis is a major killer in hospitalized patients. Coagulase-negative staphylococci (CNS) with the leading species Staphylococcus epidermidis are the most frequent causes of nosocomial sepsis, with most infectious isolates being methicillin resistant. However, which bacterial factors underlie the pathogenesis of CNS sepsis is unknown. While it has been commonly believed that invariant structures on the surface of CNS trigger sepsis by causing an over-reaction of the immune system, we show here that sepsis caused my methicillin-resistant S. epidermidis is to a large extent mediated by the methicillin resistance island-encoded peptide toxin, PSM-mec. PSM-mec contributed to bacterial survival in whole human blood and resistance to neutrophil-mediated killing, and caused significantly increased mortality and cytokine expression in a mouse sepsis model. Furthermore, we show that the PSM-mec peptide itself, rather than the regulatory RNA in which its gene is embedded, is responsible for the observed virulence phenotype. While toxins have never been clearly indicated in CNS infections, our study shows that an important type of infection caused by the predominant CNS species, S. epidermidis, is mediated to a large extent by a toxin. Of note, these findings suggest that CNS infections may be amenable to virulence-targeted drug development approaches. We used microarrays to detail the global gene expression between S. epidermidis strain Rp62A and S. epidermidis strain Rp62A isogenic Δpsm-mec deletion mutants
Project description:We use the zebrafish embryo model to study the innate immune response against Staphylococcus epidermidis. Therefore, we injected S. epidermidis into the yolk at 2 hpf and took samples at 5 days post injection.
Project description:The custom-made S. epidermidis GeneChips(Shanghai Biochip Co., Ltd) included qualifiers representing open reading frame (ORF) sequences identified in the genomes of the S. epidermidis strain RP62A, as well as unique ORFs in S. epidermidis strain 12228. The GeneChips were composed of cDNA array containing PCR products of 2316 genes and oligonucleotide array containing 252 genes.Two-component regulatory systems (TCSs) play a pivotal role in bacterial adaptation, survival, and virulence by sensing changes in the external environment and modulating gene expression in response to a variety of stimuli.To investigate the regulatory role of LytSR, one of the TCSs identified in the genomes of S. epidermidis, we used the GeneChips to perform a transcriptional profile analysis of the wild strain and lytSR mutant.
Project description:We sequenced mRNA from three independent biological replicates of Staphylococcus epidermidis biofilms with different proportion of dormant cells.
Project description:Background: Lysine succinylation is a newly identified PTM, which exists widely from prokaryotes to eukaryotes and participates in various cellular processes, especially in the metabolic processes. Staphylococcus epidermidis is a commensal bacterium in the skin, which attracts more attention as a pathogen, especially in immunocompromised patients and neonates by attaching to medical devices and forming biofilms. However, the significance of lysine succinylation in proteins of Staphylococcus epidermidis has not been investigated. Materials and methods: Using antibody affinity enrichment followed by LC-MS/MS analysis, we examined the succinylome of Staphylococcus epidermidis (ATCC®12228™). Then, bioinformatics analysis was performed, including Gene Ontology, KEGG enrichment, motif characterization, secondary structure, protein-protein interaction, and BLAST analysis. Results: A total of 1557 succinylated lysine sites in 649 proteins were identified in Staphylococcus epidermidis (ATCC 12228). Among these succinylation proteins, GO annotation showed that proteins related to metabolic processes and binding activity accounted for the most based on the analysis of biological process and molecular function, respectively. KEGG pathway characterization indicated that proteins associated with the glycolysis/ gluconeogenesis, and citrate cycle (TCA cycle) pathway were more likely to be succinylated. Moreover, 13 conserved motifs were identified. The specific motif KsuD was conserved in model prokaryotes and eukaryotes. Succinylated proteins with this motif were highly enriched in the glycolysis/gluconeogenesis pathway. One succinylation site(K144) was identified in S-ribosylhomocysteine lyase, a key enzyme in the quorum sensing system, indicating the regulatory role succinylation may play in bacterial processes. Furthermore, 15 succinyltransferases and 18 desuccinylases(erasers) were predicted in S.epidermidis by BLAST analysis. Conclusions: We performed the first comprehensive profile of succinylation in Staphylococcus epidermidis and illustrated the significant role succinylation may play in energy metabolism, QS system, and other bacterial behaviors. This study may be a fundamental basis to investigate the underlying mechanisms of colonization, virulence, and infection of S. epidermidis, as well as provide a new insight into regulatory effects succinylation may lay on metabolic processes.