Ler regulation in EPEC
Ontology highlight
ABSTRACT:
ORGANISM(S): Escherichia coli O157:H7 str. EDL933 Escherichia coli O127:H6 str. E2348/69
PROVIDER: GSE38876 | GEO | 2013/03/31
SECONDARY ACCESSION(S): PRJNA169132
REPOSITORIES: GEO
Similar Datasets
Project description:Transcriptional profiling of wt and ler- EPEC and O157 E. coli strains at mid log and early stationary growth phases wt vs. Ler- at OD 0.3 and 0.9. Biological replicates: 4 independently grown. Four replicates per array.
2013-03-31 | E-GEOD-38876 | biostudies-arrayexpress
Project description:Fis is a nucleoid-associated protein in E. coli that is abundant during early logarithmic growth in rich medium but is in short supply during stationary phase. Its role as a transcriptional regulator has been demonstrated for an increasing number of genes. In order to gain insight into the global effects of Fis on E. coli gene expression during different stages of growth in rich medium, DNA microarray analyses were conducted in fis and wild type strains during early log, mid log, late log, and stationary growth phases. We used microarrays to detail the global impact of Fis on gene expression in Escherichia coli Keywords: time course
2007-08-15 | GSE7380 | GEO
Project description:Fis is a nucleoid-associated protein in E. coli that is abundant during early logarithmic growth in rich medium but is in short supply during stationary phase. Its role as a transcriptional regulator has been demonstrated for an increasing number of genes. In order to gain insight into the global effects of Fis on E. coli gene expression during different stages of growth in rich medium, DNA microarray analyses were conducted in fis and wild type strains during early log, mid log, late log, and stationary growth phases. We used microarrays to detail the global impact of Fis on gene expression in Escherichia coli Keywords: time course
2007-08-15 | GSE7379 | GEO
Project description:Integrating laterally acquired virulence genes into the backbone regulatory network is important for the pathogenesis of Escherichia coli O157:H7, which has captured many virulence genes through horizontal transfer during evolution. GadE is an essential transcriptional activator of glutamate decarboxylase (GAD) system, the most efficient acid resistance mechanism in E. coli. The full contribution of GadE to the acid resistance and virulence of pathogenic E. coli O157:H7 remains largely unknown. We inactivated gadE in E. coli O157:H7 Sakai and compared global transcription profiles with that of wild type in exponential and stationary phases of growth using microarrays containing 6088 ORFs from three E. coli genomes. gadE inactivation significantly altered the expression of 60 genes independent of growth phase and 122 genes in a growth phase-dependent manner. Inactivation of gadE markedly down-regulated the expression of gadA, gadB, gadC and many acid fitness island genes in a growth phase-dependent manner. Nineteen genes encoded on the locus of enterocyte effacement (LEE), including ler, showed a significant increase in expression upon gadE inactivation. Altogether, our data indicate that GadE is critical for acid resistance of E. coli O157:H7 and plays an important role in virulence by down-regulating expression of LEE.
2008-10-11 | GSE13132 | GEO
Project description:Fis is a nucleoid-associated protein in E. coli that is abundant during early logarithmic growth in rich medium but is in short supply during stationary phase. Its role as a transcriptional regulator has been demonstrated for an increasing number of genes. In order to gain insight into the global effects of Fis on E. coli gene expression during different stages of growth in rich medium, DNA microarray analyses were conducted in fis and wild type strains during early log, mid log, late log, and stationary growth phases. We used microarrays to detail the global impact of Fis on gene expression in Escherichia coli Experiment Overall Design: E.coli cells were were grown and samples were taken at different times during growth: 90 min (early logarithmic phase), 150 min (mid-logarithmic phase), 240 min (late logarithmic phase), and 360 min (early stationary phase) for RNA extraction and hybridization on Affymetrix microarrays. This was done in triplicate and the raw data was analyzed using Microarray Analysis Suite version 5.0 (Affymetrix).
2008-06-15 | E-GEOD-7379 | biostudies-arrayexpress
Project description:Fis is a nucleoid-associated protein in E. coli that is abundant during early logarithmic growth in rich medium but is in short supply during stationary phase. Its role as a transcriptional regulator has been demonstrated for an increasing number of genes. In order to gain insight into the global effects of Fis on E. coli gene expression during different stages of growth in rich medium, DNA microarray analyses were conducted in fis and wild type strains during early log, mid log, late log, and stationary growth phases. We used microarrays to detail the global impact of Fis on gene expression in Escherichia coli Experiment Overall Design: E.coli cells were were grown and samples were taken at different times during growth: 90 min (early logarithmic phase), 150 min (mid-logarithmic phase), 240 min (late logarithmic phase), and 360 min (early stationary phase) for RNA extraction and hybridization on Affymetrix microarrays. This was done in triplicate and the raw data was analyzed using Microarray Analysis Suite version 5.0 (Affymetrix).
2008-06-15 | E-GEOD-7380 | biostudies-arrayexpress
Project description:Escherichia coli O157:H7 is a food-borne pathogen that causes bloody diarrhea and hemolytic uremic syndrome. Hfq is an sRNA chaperone protein that is involved in post-transcriptional regulation of virulence genes in pathogenic bacteria. In EHEC strain EDL933, Hfq acts a negative regulator of the locus of enterocyte effacement (LEE) that encodes most of the proteins involved in type three secretion and attaching and effacing lesions. We deleted hfq in E. coli O157:H7 strain 86-24 and compared global transcription profiles of the hfq mutant to the wild type strain in exponential growth phase. Deletion of hfq affected transcription of genes common to nonpathogenic and pathogenic strains of E. coli as well as pathogen-specific genes. Downregulated genes in the hfq mutant included ler as well as genes encoded in LEE2-5 that encode for type three secretion and AE lesion formation. Decreased expression of the LEE genes in the hfq mutant occurred at mid-, late, and stationary growth phases in both LB and DMEM media as detected by qRT-PCR. We also confirmed decreased regulation of the LEE genes by examining secreted proteins and AE lesion formation by the hfq mutant and WT strains. Deletion of hfq also caused decreased expression of the two-component system qseBC involved in inter-kingdom signaling and virulence gene regulation in EHEC as well as an increase in stx2AB expression that encodes for the deadly Shiga toxin. Altogether, these data indicate that Hfq plays a different regulatory role in EHEC 86-24 from what has been reported for EHEC strain EDL933 and that the role of Hfq in EHEC virulence regulation extends beyond the LEE.
2012-01-06 | GSE30893 | GEO
Project description:Comparison of transcript profiles of E. coli W3110 wild-type and rpoZ mutant cells to distinguish between the genes expressed either in the presence or absence of RNA polymerase omega subunit during log phase. Comparison of transcript profiles of E. coli rpoZ mutant cells with or without overproduction of episomal rpoD during the mid log, late log phases and also during transition to stationary phase.
2007-08-01 | E-MEXP-942 | biostudies-arrayexpress
Project description:Differential expression of genes in E. coli MG1655 strains with deletions of fis and hns was assessed under early-exponential, mid-exponential, transition-to-stationary and stationary phases of growth in LB medium.
2010-09-01 | E-MEXP-2838 | biostudies-arrayexpress