GEO DataSets

(Submitter supplied) Background: The Bacillus cereus Sigma B (SigB) dependent general stress response is activated via the two-component RsbKY system, which involves a phosphate transfer from RsbK to RsbY. It has been hypothesized that the Hpr-like phosphocarrier protein (Bc1009) encoded by bc1009 in the SigB gene cluster may play a role in this transfer, thereby acting as a regulator of SigB activation. Alternatively, Bc1009 may be involved in the activation of a subset of SigB regulon members. more...

Organism:

Bacillus cereus ATCC 14579

Type:

Expression profiling by array

Platform:

GPL9493

16 Samples

Download data: TXT

(Submitter supplied) The alternative sigma factor sigmaB has an important role in the acquisition of stress-resistance in many gram-positive bacteria. In the foodborne pathogen Bacillus cereus sigmaB is activated strongly upon a heat shock and other stress conditions. Here we describe the identification of the set of sigmaB-regulated genes in B. cereus by DNA microarray analysis of the transcriptome upon a mild heat shock. more...

Organism:

Bacillus cereus ATCC 14579

Type:

Expression profiling by array

Platform:

GPL4406

7 Samples

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(Submitter supplied) Bacillus subtilis is exposed to a wide range of transitory stress and starvation conditions. Here we investigate the expression changes observed in the B. subtilis wild type strain 168 and its isogenic sigB mutant(BSM29) with respect to each stress condition tested.

Organism:

Bacillus subtilis

Type:

Expression profiling by array

Platform:

GPL14719

111 Samples

Download data: TXT

(Submitter supplied) A common bacterial strategy for monitoring environmental challenges is to use two-component systems, which consist of a sensor histidine kinase (HK) and a response regulator (RR). In the food-borne pathogen Bacillus cereus, the alternative sigma factor σB is activated by the RR RsbY. Here we present strong indications that the PP2C-type phosphatase RsbY receives its input from the multi-sensor hybrid kinase BC1008 (renamed RsbK). more...

Organism:

Bacillus cereus ATCC 14579

Type:

Expression profiling by array

Platform:

GPL8114

4 Samples

Download data

(Submitter supplied) In this study, RNA-seq was used to compare the transcriptomes of Listeria monocytogenes 10403S and H7858 and corresponding ΔsigB mutants under exposure to pH 5.5 with or without bile. RNA-seq was performed on all strains and conditions in four independent biological replicates. Indexed and purified cDNA libraries (12 libraries per strains) were loaded together onto an independent flow cell without any other samples; sequencing was carried out by running Hiseq 2500 (single-end, 100-bp per read). more...

Organism:

Listeria monocytogenes

Type:

Expression profiling by high throughput sequencing

Platform:

GPL21330

32 Samples

Download data: XLSX

(Submitter supplied) In previously published work, we identified three Mycobacterium tuberculosis sigma (s) factor genes responding to heat shock (sigB, sigE and sigH ). Two of them (sigB and sigE ) also responded to SDS exposure. As these responses to stress suggested that the s factors encoded by these genes could be involved in pathogenicity, we are studying their role in physiology and virulence. In this work, we characterize a sigE mutant of M. more...

Organism:

Mycobacterium tuberculosis

Type:

Expression profiling by array

Platform:

GPL2787

15 Samples

Download data: TXT

(Submitter supplied) The foodborne pathogen Listeria monocytogenes uses a number of transcriptional regulators, including the negative regulator CtsR, to control gene expression under different environmental conditions and in response to stress. Gene expression patterns of DctsR log phase cells were compared to both wt and ictsR-mcsA log phase cells grown with 0.5mM IPTG to identify CtsR-dependent genes.We identified 62 CtsR-dependent genes that showed significant expression ratios (adj. more...

Organism:

Listeria monocytogenes; Listeria innocua

Type:

Expression profiling by array

Platform:

GPL5029

2 Samples

Download data: GPR

(Submitter supplied) The extensively studied intracellular pathogen, L. monocytogenes, is an ideal model for identifying small-molecule agents for treating bacterial infections. By selecting specific biological targets in L. monocytogenes, which are common to Gram-positive pathogens, we could extrapolate drug discovery information derived from this well-studied bacterium. Attenuating the pathogen’s virulence and stress response attributes without killing it, eliminates selective pressure caused by disruption of essential gene functions (as done by current antibiotics) and reduces the likelihood of developing microbes that are impervious to the effects of antibiotics. more...

Organism:

Listeria innocua; Listeria monocytogenes 10403S; Listeria monocytogenes

Type:

Expression profiling by array

Platform:

GPL5029

1 Sample

Download data: GPR

(Submitter supplied) Listeria monocytogenes is well known to have the ability to survive and grow under a variety of stress conditions. The ability to survive and grow under osmotic stress conditions in particular appears to be important for both growth in certain foods and food associated environments as well as for host infection. To characterize the contributions of transcriptional regulators important for stress response and virulence (i.e., Sigma B - σB and PrfA), we initially analyzed three L. more...

Organism:

Listeria monocytogenes

Type:

Expression profiling by array

Platform:

GPL4281

1 Sample

Download data: GPR

(Submitter supplied) In several gram-positive bacterial genera including Bacillus, Staphylococcus, and Listeria, sigma B (σB) has been identified as a stress-responsive alternative sigma factor responsible for initiating transcription of genes (the σB regulon) involved in response to stress-inducing environmental conditions. In L. monocytogenes, a foodborne pathogen of considerable threat to public health and the food industry, σB is involved in regulation of stress response and virulence gene expression. more...

Organism:

Listeria monocytogenes; Listeria innocua

Type:

Expression profiling by array

Platform:

GPL5029

4 Samples

Download data: GPR

(Submitter supplied) Listeria monocytogenes strains classify into at least three distinct phylogenetic lineages. Correlations exist between lineage classification and source of bacterial isolation, e.g., human clinical and food isolates usually classify into either lineage I or II, however, human clinical isolates are over-represented in lineage I while food isolates are over-represented in lineage II. σB, a transcriptional regulator previously demonstrated to contribute to environmental stress response and virulence in L. more...

Organism:

Listeria monocytogenes

Type:

Expression profiling by array

Platform:

GPL4281

4 Samples

Download data: GPR

(Submitter supplied) The numerous sigma factors present in Mycobacterium tuberculosis (MTB) are indicative of adaptability to different environmental conditions. In this report we describe the sigma factor B (sigB) regulon and the phenotypes of a MTB sigB mutant strain exposed to different stresses like SDS and Diamide. This experiment set compares expression profiles between H37Rv wild type and H37Rv sigB null mutant as well as under different stress conditions. more...

Organism:

Mycobacterium tuberculosis

Type:

Expression profiling by array

Platform:

GPL8523

36 Samples

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(Submitter supplied) Acclimation of cyanobacterium Synechocystis sp. PCC6803 to suboptimal conditions is largely dependent on adjustments of gene expression, which is highly controlled by the σ factor subunits of RNA polymerase (RNAP). The SigB and SigD σ factors are close homologues. Here we show that sigB and sigD genes are both induced in bright light and high temperature stresses. Comparison of transcriptomes of the control strain (CS), ΔsigB, ΔsigD, ΔsigBCE (SigD is an only functional group 2 σ factor), and ΔsigCDE (SigD is an only functional group 2 σ factor) strains in standard, bright light and high temperature conditions revealed that the SigB and SigD factors regulate different set of genes, and that SigB and SigD regulons are highly dependent on stress conditions. more...

Organism:

Synechocystis sp. PCC 6803

Type:

Expression profiling by high throughput sequencing

Platform:

GPL31128

45 Samples

Download data: TSV

(Submitter supplied) Comparing the transcriptional responses of Bacillus subtilis strains WN624 and WN1106 at 5 kPa and 101 kPa. WN1106 is a 5 kPa-evolved strain with increased fitness compared to ancestor-WN624 strain at 5 kPa. This experiment probed the difference in response when the strains are grown at 5 kPa.

Organism:

Bacillus subtilis subsp. subtilis str. 168

Type:

Expression profiling by array

Platform:

GPL17693

8 Samples

Download data: TXT

(Submitter supplied) In Gram-positive organisms the general stress response is regulated by the alternative sigma factor sigma B (σB). In C. difficile this sigma factor has been implicated in protection against stressors such as reactive oxygen species and antimicrobial compounds. Here, we show that an anti-σB antibody can be used to demonstrate overexpression of σB in C. difficile and that this overexpression is tolerated for short periods of time, despite its toxicity. more...

Organism:

Clostridioides difficile 630

Type:

Expression profiling by array

Platform:

GPL25054

16 Samples

Download data: TXT, XLS

(Submitter supplied) Background. Infections caused by Staphylococcus aureus are associated with significant morbidity and mortality and are an increasing threat not only in hospital settings. The expression of the staphylococcal virulence factor repertoire is known to be affected by the alternative sigma factor B (SigB). However, its impact during infection still is a matter of debate. Methods. Kidney tissue of controls or mice infected with S. more...

Organism:

Mus musculus

Type:

Expression profiling by array

Platform:

GPL6246

24 Samples

Download data: CEL

(Submitter supplied) RpoN was shown to have a pleiotropic role in different microorganisms. This study was performed to elucidate role in B. cereus. In this study we compared the transcriptomic profiles of the WT, rpoN mutant and the complemented strain in aerated and static growth conditions.

Organism:

Bacillus cereus ATCC 14579

Type:

Expression profiling by array

Platform:

GPL19768

24 Samples

Download data: TXT

(Submitter supplied) Abstract of associated manuscript: The Bacillus subtilis extracytoplasmic function (ECF) sigma(M) factor is activated by cell envelope stress elicited by antibiotics, and by acid, heat, ethanol and superoxide stresses. Here, we have used several complementary approaches to identify genes controlled by sigma(M). In many cases, expression is only partially dependent on sigma(M) because of both overlapping promoter recognition with other ECF sigma factors and the presence of additional promoter elements. more...

Organism:

Bacillus subtilis

Type:

Expression profiling by array

Platform:

GPL7420

14 Samples

Download data: GPR

(Submitter supplied) To characterize regulons of alternative sigma factor SigH, SigL, and SigC in Listeria monocytogenes, in-frame mutant strains were created in the 10403S background. Regulons controlled by these 3 alternative sigma factors were characterized by whole-genome microarrays. The L. monocytogenes 10403S wild type and sigma factor null mutation strains were grown at 37 °C to stationary phase (defined in this study as growth to OD600 = 1.0, followed by incubation for an additional 3 h) prior to RNA isolation. more...

Organism:

Listeria monocytogenes; Listeria innocua

Type:

Expression profiling by array

Platform:

GPL5029

5 Samples

Download data: GPR, TXT

(Submitter supplied) The foodborne pathogen Listeria monocytogenes uses a number of transcriptional regulators, including the negative regulator HrcA, to control gene expression under different environmental conditions and in response to stress. Gene expression patterns of DhrcA stationary phase cells were compared to wt to identify hrcA-dependent genes. We identified 61 HrcA-dependent genes that showed significant expression ratios (adj. more...

Organism:

Listeria monocytogenes; Listeria innocua

Type:

Expression profiling by array

Platform:

GPL5029

1 Sample

Download data: GPR