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:Streptococcus pyogenes, otherwise known as Group A Streptococcus (GAS), is an important and highly adaptable human pathogen with the ability to cause both superficial and severe diseases. Understanding how S. pyogenes senses and responds to its environment will likely aid in determining how it causes a breadth of diseases. One regulatory network involved in GAS’s ability to sense and respond to the changing environment is the Rgg2/3 quorum sensing (QS) system, which responds to metal and carbohydrate availability and regulates changes to the bacterial surface. To better understand the impact of Rgg2/3 QS on S. pyogenes physiology, we performed RNA-seq and TMT (tandem mass tag)-LC-MS/MS analysis on cells in which this system was induced with SHP pheromone or disrupted. Primary findings confirmed that pheromone stimulation in wildtype cultures is limited to the induction of operons whose promoters contain previously determined Rgg2/3 binding sequences. However, a deletion mutant of rgg3, a strain that endogenously produces elevated amounts of pheromone, led to extended alterations of the transcriptome and proteome, ostensibly by stress-induced pathways. Under such exaggerated pheromone conditions, a connection was identified between Rgg2/3 and the stringent response. Mutation of relA, the bifunctional guanosine tetra- and penta-phosphate nucleoside synthetase/hydrolase, and alarmone synthase genes sasA and sasB, impacted culture doubling times and disabled induction of Rgg2/3 in response to mannose, while manipulation of Rgg2/3 signaling modestly altered nucleotide levels. Our findings indicate that excessive pheromone production or exposure places stress on GAS resulting in an indirect altered proteome and transcriptome beyond primary pheromone signaling.
Project description:The small prophage protein paratox (Prx) from Streptococcus pyogenes strain MGAS315 was used as bait in pull-down assays with bacterial lysates to discover potential binding partners. Bacterial lysates analyzed included MGAS315 stimulated with the quorum sensing pheromone XIP-- that induces natural competence, and MGAS315 stimulated with mitomycin C which induces bacteriophage protein expression.
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) is an important human pathogen that causes a variety of infectious diseases and sequelae. Recent studies showed virulence factor expression was controlled at multiple levels, including the post-transcriptional regulation. In this study, we examined the global half-lives of S. pyogenes mRNAs and explored the role RNase Y played in mRNA metabolism with microarray analysis. key word: genetic modification
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.