Listeria monocytogenes transcriptional response to bile
Ontology highlight
ABSTRACT:
ORGANISM(S): Listeria monocytogenes Listeria monocytogenes serotype 4b str. H7858 Listeria monocytogenes serotype 1/2a str. F6854 Listeria monocytogenes EGD-e Listeria monocytogenes serotype 4b str. F2365
PROVIDER: GSE28507 | GEO | 2011/04/12
SECONDARY ACCESSION(S): PRJNA138987
REPOSITORIES: GEO
Similar Datasets
Project description:These studies were designed to examine the acute Listeria monocytogenes transcriptional response to mammalian (porcine) bile. Triplicate WT Listeria monocytogenes (strain 10403S) were grown to mid-log in BHI at 37 °C. Samples were divided, and either treated or not treated by addition of porcine bile (Sigma, to 1% final) for 30 minutes.
2011-04-12 | E-GEOD-28507 | biostudies-arrayexpress
Project description:These studies were designed to examine the transcription of Listeria monocytogenes strains 10403S and LO28 during intracellular replication in mammalian macrophages.
2011-12-02 | GSE34083 | GEO
Project description:These studies were designed to examine the transcription of Listeria monocytogenes strains 10403S and LO28 during intracellular replication in mammalian macrophages. Duplicate WT Listeria monocytogenes (strains 10403S and LO28) were used to infect mouse bone marrow-derived macrophages (BMMs). Bacterial RNA was harvested at 4 hours post-infection.
2011-12-02 | E-GEOD-34083 | biostudies-arrayexpress
Project description:Listeria monocytogenes is a gram-positive, facultative anaerobe food-borne pathogen that is the causative agent of listeriosis. Upon ingestion, L. monocytogenes is subjected to a variety of non-specific host defenses such as bile. The main component of bile is bile salts which is known to be bactericidal through inducing DNA damage, oxidative damage, membrane instability, and protein misfolding. Previous studies have focused mainly on aerobic conditions; however the human GI tract is an environment ranging from microaerophilic to anaerobic. The bile salt hydrolase, an enzyme known to reduce toxicity of bile through hydrolysis, has been shown to have an increase in activity under anaerobic conditions. Therefore, the purpose of this study was to determine the effect of oxygen on bile resistance and determine the bile specific proteome that is responsible for this. To do this, we performed survival assays on virulent strains: F2365, 10403S, EGDe and avirulent strain, HCC23. Results showed an increase in viability for all virulent strains when exposed to porcine bile under anaerobic conditions. Interestingly, an increase in resistance was seen in HCC23 only under aerobic conditions. We then used a total proteomic analysis approach to compare the bile specific proteome under both aerobic and anaerobic conditions. Results showed many difference between all strains including an increase in abundance of proteins associated with stress responses, repair, cell morphology, and cell division under anaerobic conditions. Response to bile salt stress showed to be strain dependent. This study not only identified proteins responsible for L. monocytogenes bile resistance but also differerences between aerobic and anaerobic conditions thus suggesting that oxygen availability is not only a stressor but in some way providing assistance to overcoming bile salts.
2017-05-03 | PXD002243 | Pride
Project description:Listeria monocytogenes transcriptional response to bile
| PRJNA138987 | ENA
Project description:Listeria monocytogenes is a gram-positive, food-borne pathogen responsible for invasive infections with high overall mortality. Early host defenses encountered by L. monocytogenes following ingestion include low pH of the stomach and bile present in the small intestinal lumen. We hypothesized that “epidemic” strains are better able to withstand exposure to low pH and bile encountered in the gastrointestinal tract as compared to most “environmental” strains. Furthermore, we hypothesized that epidemic and environmental strains would have distinct transcriptional programs upon exposure to these conditions. Our treatments included 1 hr exposure to acid (pH 5.5 and 3.5) and bile (0.3%) stress. Strains were pre-exposed to pH 5.5 (1 hr) before being treated with pH 3.5. We used a collection of 12 previously characterized epidemic and environmental strains and each strainXtreatment combination included 3 biological replicates for each microarray experiment. All microarray experiments were two color competitive hybridizations that paired experimental conditions with the same strain at neutral pH for acid stress and pH 5.5 for bile stress. Transcriptomes of environmental strains exposed to acid and bile stress showed remarkably greater number of genes with differences of ≥2-fold expression levels as compared to epidemic strains (5 and 7, respectively). Environmental strains were characterized by up-regulation of several stress related genes and down-regulation of several cell envelope biosynthesis and virulence related genes, suggesting that complex regulatory networks orchestrate the cellular changes in the environmental strains to overcome stressful environments. The transcriptome of epidemic strains, in contrast, showed muted responses to these stress conditions implying their pre-adaptability to acid and bile stress encountered during natural infection that may enable epidemic strains to survive and become “primed” for subsequent colonization and infection in the lower gastrointestinal tract. Keywords: stress response, comparative transcriptomics, acid-adaptation, differential virulence, acid-stress response, bile-stress response
2009-06-15 | GSE10603 | GEO
Project description: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. P < 0.05), with ≥ 1.5-fold differential expression between ΔhrcA and wt. Combined with microarray analysis, Hidden Markov Model searches show HrcA directly repress at least 8 genes. Keywords: Listeria monocytogenes, HrcA regulon, stationary phase
2007-11-03 | GSE7517 | GEO
Project description: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. P < 0.05), with ≥ 1.5-fold differential expression either between ΔctsR and wt or between ΔctsR and ictsR-mcsA. Keywords: Listeria monocytogenes, CtsR regulon, log phase
2007-10-14 | GSE7514 | GEO
Project description:Listeria monocytogenes strain 10403S has been studied extensively for stress response activity toward multiple stressors (acid, osmotic, cold, high temperature, etc.) as well as multiple stress regulons (SigB, CtsR, HrcA, etc.). Here we aimed to determine the transcriptional response of Listeria monocytogenes in early log phase towards the strong oxidative stress imposed by ClO2. The elucidation of such a response allows for further a more completel understanding of the mechanism of inactivation by sanitizers, specifically ClO2.
2014-03-07 | GSE48187 | GEO
Project description:Several Toll-like receptors are activated by Listeria monocytogenes infection, resulting in the activation of MyD88 dependent signaling pathway. However, the negative role of MyD88 in gene expresson is unclear. To address this, we performed microarray analysis of mRNAs from WT or MyD88-/- peritoneal macrophages infected with Listeria monocytogenes.
2014-06-29 | GSE52115 | GEO