Project description:Staphylococcus aureus is a common human and animal opportunistic pathogen. In humans nasal carriage of S. aureus is a risk factor for various infections. Methicillin-resistant S. aureus ST398 is highly prevalent in pigs in Europe and North America. The mechanism of successful pig colonization by MRSA ST398 is poorly understood. Previously, we developed a nasal colonization model of porcine nasal mucosa explants to identify molecular traits involved in nasal MRSA colonization of pigs. Here, we report the analysis of the transcriptome of MRSA ST398 strain S0462 during colonization on the explant epithelium. Major regulated genes were encoding metabolic processes and regulation of these genes represents metabolic adaptation to nasal mucosa explants. Colonization was not accompanied by significant changes in transcripts of main virulence associated genes or known human colonization factors. Here, we document regulation of two genes which have potential influence on S. aureus colonization; cysteine extracellular proteinase (scpA) and von Willebrand factor-binding protein (vwbp, located on SaPIbov5). Colonization with isogenic-deletion strains (Δvwbp and ΔscpA) did not alter the nasal S. aureus colonization compared to wild type. Our results suggest that nasal colonization with MRSA ST398 is a complex event that is accompanied with changes in bacterial gene expression regulation and metabolic adaptation.
Project description:To determine if significant genomic changes are associated with the development of vancomycin intermediate Staphylococcus aureus, genomic DNA microarrays were performed to compare the initial vancomycin susceptible Staphylococcus aureus (VSSA) and a related vancomycin intermediate Staphylococcus aureus (VISA) isolate from five unique patients (five isolate pairs). Keywords: comparative genomic hybridization
Project description:Nasal colonization is well described; however, we have limited knowledge about S. aureus throat colonization. The main objective of this project was to explore differentially expressed genes (DEGs) in S. aureus throat isolate TR145 exposed for 1 or 3 hours (h) to human tonsil epithelial cells (HTEpiC) by using RNA sequencing (RNA-seq) and pathway analysis. We have shown the suitability of using HTEpiC as an in vitro model for investigating key determinants in S. aureus during co-incubation with the HTEpiC cells. Among the DEGs were genes encoding proteins involved in adhesion and immune evasion, as well as iron acquisition and transport. As their expression is induced upon meeting with the HTEpiC, they might be explored further for future targets for intervention to prevent either colonization or infection in the throat region.
Project description:To investigate the function NarGHJI in the regulation of the expression of virulence factors, we constructed a narGHJI mutant by targeted deletion of narG in MRSA isolate USA300 LAC We then performed gene expression profiling analysis using data obtained from RNA-seq of of two different strains at early exponential (OD600 = 0.5).
Project description:Staphylococcus aureus is a common human and animal opportunistic pathogen. In humans nasal carriage of S. aureus is a risk factor for various infections. Methicillin-resistant S. aureus ST398 is highly prevalent in pigs in Europe and North America. The mechanism of successful pig colonization by MRSA ST398 is poorly understood. Previously, we developed a nasal colonization model of porcine nasal mucosa explants to identify molecular traits involved in nasal MRSA colonization of pigs. Here, we report the analysis of the transcriptome of MRSA ST398 strain S0462 during colonization on the explant epithelium. Major regulated genes were encoding metabolic processes and regulation of these genes represents metabolic adaptation to nasal mucosa explants. Colonization was not accompanied by significant changes in transcripts of main virulence associated genes or known human colonization factors. Here, we document regulation of two genes which have potential influence on S. aureus colonization; cysteine extracellular proteinase (scpA) and von Willebrand factor-binding protein (vwbp, located on SaPIbov5). Colonization with isogenic-deletion strains (Î?vwbp and Î?scpA) did not alter the nasal S. aureus colonization compared to wild type. Our results suggest that nasal colonization with MRSA ST398 is a complex event that is accompanied with changes in bacterial gene expression regulation and metabolic adaptation. Number of the samples: 5 (timepoint 0 min, 30 min, 60 min, 90 min and 180 min) in 4 replicates. 4 control samples
Project description:Transcriptional profiling of the small colony variant (SCV) S. aureus isolate (JKD6229) compared to the parent isolate with a normal phenotype (JKD6210). Both isolates were from a patient with persistent S. aureus infection, and the SCV strain arose during failed antibiotic therapy.