Streptococcus sp. 'group A'
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA273454 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| SRR1770460.fastq.gz | Fastqsanger.gz | |||
| SRR1770460_1.fastq.gz | Fastqsanger.gz | |||
| SRR1770460_2.fastq.gz | Fastqsanger.gz | |||
| SRR1770470.fastq.gz | Fastqsanger.gz | |||
| SRR1770470_1.fastq.gz | Fastqsanger.gz |
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Similar Datasets
Project description:Group A Streptococcus (GAS) is a human-adapted pathogen responsible for a variety of diseases. The GAS M1UK lineage has contributed significantly to the recently reported increases in scarlet fever and invasive infections, however the basis for its evolutionary success is not yet fully understood. During the transition to systemic disease, the M1 serotype is known to give rise to spontaneous mutations in the CovRS two-component transcriptional regulation system that confer a fitness advantage during invasive infections. Mutations that inactivate CovS function result in the de-repression of key GAS virulence factors such as Streptolysin O (SLO), a pore-forming toxin and major trigger of inflammasome/interleukin-1-dependent inflammation. Conversely, expression of the streptococcal cysteine protease SpeB, which is required during initial stages of colonisation and onset of invasive disease, is typically lost in such mutants. In this study, we identified and characterised a novel covS mutation detected in three separate invasive M1UK isolates. The resulting CovSAla318Val mutation caused a significant upregulation of SLO resulting in increased inflammasome activation in human THP-1 macrophages, indicating an enhanced inflammatory potential. Surprisingly, SpeB production was unaffected. Site-directed mutagenesis was performed to assess the impact of this mutation on virulence and global gene expression. We found that the CovSAla318Val mutation led to subtle, virulence-specific changes of the CovRS regulon compared to previously characterised covS mutations, highlighting an unappreciated level of complexity in CovRS-dependent gene regulation. Continued longitudinal surveillance is warranted to determine whether this novel covS mutation will expand in the M1UK lineage.
2024-10-28 | GSE280498 | GEO
Project description:We investigated the covS-regulation of S. pyogenes in a hypervirulent M23 strain using RNA-sequencing. The differential gene expression comparison between the covS- mutant and isogenic wild type covS+ identified altered expression of 349 (18%) genes, including a broad spectrum of virulence genes and diverse metabolic genes. The data showed that the strain achieved hypervirulence by enhancing the expression of genes responsible for invasiveness and antiphagocytosis (i.e., hasABC), by abrogating the expression of toxic genes (i.e., speB), and by compromising gene products with dispensable functions (i.e., sfb1). Meanwhile, we found that covS also regulated diverse kinds of metabolic genes that maximized nutrient utilization and energy metabolism during growth and dissemination. From constructing a genome-scale metabolic model, we identified fourteen non-redundant metabolic gene modules, which constitute unique sources for specific nutrients. These genes were probably essential for pathogen growth and virulence. In general, this study provided quantitative transcriptomic signatures of the covS regulation in a hypervirulent S. pyogenes strain and addressed major aspects of the covS-modulated virulent mechanisms. Examination of expression profiling of covS- mutant strain and isogenic wild type covS+ at different growth stages.
2015-08-05 | E-GEOD-67533 | biostudies-arrayexpress
Project description:Evaluation of ccpA deletion on global gene expression of three M serotype strains of group A streptococcus
| PRJNA330717 | ENA
Project description:We investigated the covS-regulation of S. pyogenes in a hypervirulent M23 strain using RNA-sequencing. The differential gene expression comparison between the covS- mutant and isogenic wild type covS+ identified altered expression of 349 (18%) genes, including a broad spectrum of virulence genes and diverse metabolic genes. The data showed that the strain achieved hypervirulence by enhancing the expression of genes responsible for invasiveness and antiphagocytosis (i.e., hasABC), by abrogating the expression of toxic genes (i.e., speB), and by compromising gene products with dispensable functions (i.e., sfb1). Meanwhile, we found that covS also regulated diverse kinds of metabolic genes that maximized nutrient utilization and energy metabolism during growth and dissemination. From constructing a genome-scale metabolic model, we identified fourteen non-redundant metabolic gene modules, which constitute unique sources for specific nutrients. These genes were probably essential for pathogen growth and virulence. In general, this study provided quantitative transcriptomic signatures of the covS regulation in a hypervirulent S. pyogenes strain and addressed major aspects of the covS-modulated virulent mechanisms.
2015-08-05 | GSE67533 | GEO
Project description:We sought to determine how single amino acid changes in the active site of CovS autophosphorylation and subsequent phosphorylation of the response regulator CovR affect the gene expression profile of group A streptococcus There were 6 strains analyzed, each in quadruplicate replicates: 1) wild-type GAS; 2) covS deletion strain; 3) covS with alanine at AA 280; 4) covS with valine at AA 281; 5) covS with valine at AA 284; 6) covS with alanine at AA 457
2015-01-24 | E-GEOD-65226 | biostudies-arrayexpress
Project description:We performed CovR ChIP-seq analysis in the emm1 strain MGAS2221 and its CovS kinase deficient derivative strain 2221-CovS-E281A. We identified that CovR bound in the promoter regions of nearly all virulence factor encoding genes in the CovR regulon. Additionally, direct CovR binding was observed for numerous genes encoding proteins involved in amino acid metabolism, but we found limited direct CovR binding to genes encoding other transcriptional regulators. The consensus sequence AATRANAAAARVABTAAA was present in the promoters of genes directly regulated by CovR, and mutations of highly conserved positions within this motif relieved CovR repression of the hasA and M2221_0187 promoters. Analysis of strain 2221-CovS-E281A revealed that binding of CovR at repressed, but not activated, promoters is highly dependent on CovR~P state. CovR repressed virulence factor encoding genes could be grouped dependent on how variation in CovR~P differentially impacted DNA binding and gene transcript levels.
2022-01-03 | GSE192795 | GEO
Project description:We sought to determine how single amino acid changes in the active site of CovS autophosphorylation and subsequent phosphorylation of the response regulator CovR affect the gene expression profile of group A streptococcus
2015-01-24 | GSE65226 | GEO
Project description:Analysis of the group A Streptococcus CcpA Transcriptome
| PRJNA108349 | ENA
Project description:Group B Streptococcus (GBS) strain CNCTC 10/84 was modified to have specific mutations to the cas9 gene: allelic exchange replacement with a chloramphenicol resistance marker (Cas9 knockout), D10A and H845A (catalytically inactive dCas9), or R1339A and R1441A (sCas9 unable to scan for protospacer adjacent motifs). Wild type (WT) and mutant strains were grown in biological triplicate samples and used for RNA purification at two growth timepoints: OD600=0.6 and OD600=1.2. Additionally, CNCTC 10/84 dCas9 and A909 dCas9 were transformed with p3015b expression plasmids expressing sgRNA cassettes designed to downregulate the cyl operon in CNCTC 10/84 dCas9 and the covR/covS two-component system in A909 dCas9. Triplicate samples were grown alongside control transformants bearing "sham" sgRNA plasmid. RNA was purified at OD600=1.2. All RNA samples were used for RNA-seq and subsequent bioinformatic analyses.
2023-05-15 | GSE226236 | GEO
Project description:The control of virulence two-component gene regulatory system (CovRS) is critical to the pathogenesis of many medically important streptococci. In emm1 group A streptococci (GAS), CovR directly binds the promoters of numerous GAS virulence factor encoding genes. Elimination of CovS phosphatase activity increases CovR phosphorylation (CovR~P) levels and abrogates GAS virulence. Given the emm type-specific diversity of CovRS function, herein we used ChIP-seq to define global CovR DNA occupancy in the wild-type emm3 strain MGAS10870 (medium CovR~P) and its CovS phosphatase-negative derivative 10870-CovS-T284A (high CovR~P). In the wild-type emm3 strain, 89% of the previously identified emm1 CovR binding sites present in the emm3 genome were also enriched; additionally, we ascertained unique CovR binding, primarily to genes in mobile genetic elements and other sites of inter-strain chromosomal differences. Elimination of phosphatase activity specifically increased CovR occupancy at the promoters of a broad array of CovR repressed virulence factor encoding genes, including those encoding the key GAS regulator Mga and M protein. However, a limited number of promoters had augmented enrichment at low CovR~P levels. Differential motif searches using sequences enriched at high vs. low CovR~P levels revealed two distinct binding patterns. At high CovR~P, a pseudo-palindromic AT-rich consensus sequence consistent with CovR binding as a dimer was determined. Conversely, sequences specifically enriched at low CovR~P contained isolated “ATTARA” motifs suggesting an interaction with a monomer. These data extend understanding of global CovR DNA occupancy beyond emm1 GAS and provide a mechanism for previous observations regarding hypovirulence induced by CovS phosphatase abrogation.
2023-05-31 | GSE230870 | GEO