Project description:Whole genome expression profile comparing MGAS315 treated with XIP pheromone versus vehicle-treated cells Interpretations are described further in the manuscript to be submitted: authors Mashburn-Warren, Morrison, and Federle. Title: The Cryptic Competence Pathway in Streptococcus pyogenes is Controlled by a Peptide Pheromone. A two chip study using total RNA recovered from three separate cultures of Streptococcus pyogenes MGAS315, each treated with either XIP pheromone or with vehicle; RNA preparation of cultures receiving same type of treatment were pooled using equivalent amounts of RNA from each culture. RNA pools were fluorescently labeled and hybridized to arrays designed to the S. pyogenes NZ131 genome.
Project description:Whole genome expression profile comparing MGAS315 treated with XIP pheromone versus vehicle-treated cells Interpretations are described further in the manuscript to be submitted: authors Mashburn-Warren, Morrison, and Federle. Title: The Cryptic Competence Pathway in Streptococcus pyogenes is Controlled by a Peptide Pheromone.
Project description:In Streptococcus pyogenes, mutation of GidA results in avirulence despite the same growth rate as the wild type. To understand the basis of this effect, global transcription profiling was conducted. Keywords: Wild type vs. GidA mutant Streptococcus pyogenes
Project description:Whole genone expression profile comparing wild-type NZ131 to serR deletion mutant, grown in C-medium Mutants and interpretation are described further in the manuscript to be submitted: LaSarre and Federle, 2010. Title: Regulation and Consequence of Serine Catabolism in Streptococcus pyogenes. A two chip study using total RNA recovered from three separate wild-type cultures of Streptococcus pyogenes NZ131 and three separate mutant cultures of Streptococcus pyogenes NZ131 seR-, pooled following RNA extraction
Project description:Streptococcus pyogenes (group A Streptococcus, GAS) responds to environmental changes in a manner that results in an adaptive regulation of the transcriptome. Global transcriptional regulators are able to integrate important extracellular and intracellular information and are responsible for modulation of the transcriptional network. The roles of several global transcriptional regulators in adaptation and virulence gene expression have been described. In this study we used microarray to investigate the regulatory roles of CodY and CovRS played in Streptococcus pyogenes. keywords: genetic modification Streptococcus pyogenes NZ131 wild-type cells, ΔcodY, ΔcovRS and ΔcodYcovRS strains were grown in C-medium until mid-exponential phase or early-stationary phase. The transcriptional profile of the whole genome was examined with microarray.
Project description:Manuscript title: Zinc disrupts central carbon metabolism and capsule biosynthesis in Streptococcus pyogenes. Macrophages and neutrophils release free zinc to eliminate phagocytosed bacterial pathogens. The study investigates the effect of how zinc toxicity affects Streptococcus pyogenes. Therefore, a microarray analysis was performed in S. pyogenes cells to determine gene expression changes when exposed to high levels of zinc. We discovered that a pathway involved in tagatose-6-phosphate metabolism was upregulated when the cells are under zinc stress.
Project description:Streptococcus pyogenes (Group A Streptococcus: GAS) is a major human pathogen that causes streptococcal pharyngitis, skin and soft-tissue infections, and life-threatening conditions such as streptococcal toxic shock syndrome (STSS). A large number of virulence-related genes are encoded on GAS genomes, which are involved in host-pathogen interaction, colonization, immune invasion, and long-term survival within hosts, causing the diverse symptoms. Here, we investigated the interaction between GAS-derived extracellular vesicles and host cells in order to reveal pathogenicity mechanisms induced by GAS infection.
Project description:Clonal emergence is a major driver for changes in bacterial disease epidemiology. Recently, it has been proposed that episodic emergence of novel, hypervirulent clones of group A Streptococcus (GAS) results from horizontal gene transfer (HGT) and recombination events leading to increased expression of the cytotoxins Nga (NADase) and SLO (streptolysin O). We previously described a gene fusion event involving the gene encoding the GAS M protein (emm) and an adjacent M-like protein (enn) in the emm4 GAS population, a GAS emm type that lacks the hyaluronic acid capsule. Using whole genome sequencing of a temporally and geographically diverse set of 1,127 isolates, we discovered that the North American emm4 GAS population has undergone clonal replacement with emergent GAS strains completely replacing historical isolates by 2017. Emergent emm4 GAS strains were defined by a handful of small genetic variations, including the emm-enn gene fusion, and showed a marked in vitro growth defect compared to historical strains. In contrast to other previously described GAS clonal emergence events, emergent emm4 GAS lacked significant HGT events and showed no significant increase in transcript levels of nga/slo toxin gene via RNA sequencing and quantitative real-time PCR analysis relative to historic strains. Despite the in vitro growth differences, emergent emm4 GAS strains demonstrated hypervirulence in mouse and ex vivo growth in human blood compared to historical strains. Thus, these data detail the emergence and dissemination of a hypervirulent acapsular GAS clone defined by small genetic variation thereby defining a novel model for GAS strain replacement.
Project description:The Antibiotic Resistant Sepsis Pathogens Framework Initiative aims to develop a framework dataset of 5 sepsis pathogens (5 strains each) using an integrated application of genomic, transcriptomic, metabolomic and proteomic technologies. The pathogens included in this initiative are: Escherichia coli, Klebsiella pneumoniae complex, Staphylococcus aureus, Streptococcus pyogenes, and Streptococcus pneumoniae. This submission pertains to Streptococcus pyogenes strains 5448, SP444, HKU419, PS003 and PS006.