Legionella pneumophila transcriptomic response of hfq mutant during post-exponential phase
Ontology highlight
ABSTRACT:
ORGANISM(S): Legionella pneumophila subsp. pneumophila str. Philadelphia 1 Legionella pneumophila
PROVIDER: GSE42905 | GEO | 2013/05/21
SECONDARY ACCESSION(S): PRJNA183836
REPOSITORIES: GEO
Similar Datasets
Project description:Legionella pneumophila wild-type and hfq mutant were grown to post-exponential. The wild-type strain is used as the control. Two strains: wild-type (control) and hfq mutant (test). Three biological replicates. Ch1 is gDNA, use as a reference channel (Talaat, 2002, NAR)
2013-05-21 | E-GEOD-42905 | biostudies-arrayexpress
Project description:Legionella pneumophila cells were harvested during exponential growth (RP) and stationary growth (TP). VBNC cells were also anylzed. Protein subfractions were studied.
2015-11-13 | PXD001926 | Pride
Project description:Legionella pneumophila transcriptomic response of hfq mutant during post-exponential phase
| PRJNA183836 | ENA
Project description:Legionella pneumophila is the causative agent of Legionnaires’ disease, an acute pulmonary infection. L. pneumophila is able to infect and multiply in both phagocytic protozoan, such as Acanthamoeba castellanii, and mammalian professional phagocytes. The best-known virulence determinant used by L. pneumophila to infect host cells is a Type IVb translocation system named Icm/Dot, which is used to modify the host cell functions to the benefit of the bacteria. To date the Icm/Dot systeme is known to translocate more than 100 effectors. While the transcriptional response of Legionella to the intracellular environement of A. castelannii as already been investigated, much less is known of how Legionella reacts transcriptionnally inside human macrophages. In this study, the transcriptome of L. pneumophila was monitored during exponential and post-exponential phase in rich AYE broth and during infection of human cultured macrophages by using microarray and a RNA amplification procedure called SCOTS to allow for the study of conditions of low bacterial loads. Among the genes induced intracellularly are those involved in amino acid synthesis pathway leading to L-arginine, L-histidne and L-proline as well as many transport system involved in amino acid and iron uptake. The Icm/Dot systems is not differentially expressed inside cells compare to the E phase control but the effectors are strongly induced. The intracellular transcriptome was further used to identify putative new Icm/Dot effectors and translocation was show to occur for 3 of them. This study provides a comprehensive view of how L. pneumophila react to the human macrophages intracellular environment.
2011-01-01 | GSE23029 | GEO
Project description:This SuperSeries is composed of the following subset Series: GSE19196: Detection of predicted small RNA of Legionella pneumophila GSE19200: Gene affected by deletion of 6S RNA in post-exponential phase Refer to individual Series
2010-06-24 | E-GEOD-19451 | biostudies-arrayexpress
Project description:Legionella pneumophila was exposed for 3h to 160 ug/ml of CuO nanoparticle. Untreated samples are used as the control condition.
2013-03-04 | GSE41966 | GEO
Project description:Legionella pneumophila is the causative agent of Legionnaires’ disease, an acute pulmonary infection. L. pneumophila is able to infect and multiply in both phagocytic protozoan, such as Acanthamoeba castellanii, and mammalian professional phagocytes. The best-known virulence determinant used by L. pneumophila to infect host cells is a Type IVb translocation system named Icm/Dot, which is used to modify the host cell functions to the benefit of the bacteria. To date the Icm/Dot systeme is known to translocate more than 100 effectors. While the transcriptional response of Legionella to the intracellular environement of A. castelannii as already been investigated, much less is known of how Legionella reacts transcriptionnally inside human macrophages. In this study, the transcriptome of L. pneumophila was monitored during exponential and post-exponential phase in rich AYE broth and during infection of human cultured macrophages by using microarray and a RNA amplification procedure called SCOTS to allow for the study of conditions of low bacterial loads. Among the genes induced intracellularly are those involved in amino acid synthesis pathway leading to L-arginine, L-histidne and L-proline as well as many transport system involved in amino acid and iron uptake. The Icm/Dot systems is not differentially expressed inside cells compare to the E phase control but the effectors are strongly induced. The intracellular transcriptome was further used to identify putative new Icm/Dot effectors and translocation was show to occur for 3 of them. This study provides a comprehensive view of how L. pneumophila react to the human macrophages intracellular environment. The aim of this work was to study the gene expression profile of Legionella during infection of macrophages infected at a low multiplicity of infection (MOI). SCOTS is a method that allows amplification of small amounts of bacterial RNA from infected host cells, while discarding host cell transcripts and ribosomal RNA. Before infection, macrophages derived from the THP-1 monocyte cell line were pre-treated with antibodies against the L. pneumophila major outer membrane protein, which increases the efficiency of bacterial entry into host cells . After 2 hours of infection, the macrophages were washed and treated with gentamicin for 1 hour, to synchronize the infection and kill extracellular bacteria, and cells were washed 3 times and fresh medium was added. Samples for the first time point (T0) were collected after the gentamicin treatment. Samples were also collected after 6h (T6) and 18h (T18). Samples from all conditions, including growth in AYE broth to exponential (E) or post exponential (PE) phase, were treated with three consecutive rounds of SCOTS and the resulting cDNA was labeled and hybridized to the microarray slides. As a reference channel, labeled gDNA was also hybridized. For each condition studied, three independent biological replicates and two technical replicates were analyzed, resulting in six replicates for each condition. The data was background subtracted and normalized by calculating the contribution of each spot to the total intensity and the ratio to gDNA was recorded. A one tailed student's T test was used for statistical analysis and the ratio between test conditions (PE, T0, T6 and T18) and the control conditions (E phase or T0) was calculated.
2011-01-01 | E-GEOD-23029 | biostudies-arrayexpress
Project description:Legionella pneumophila (corby) infected blood derived macrophages are infected in a time course experiment (24& 48hours)
2019-01-25 | GSE125559 | GEO
Project description:Legionella pneumophila Philadelphia-1 strain was grown to stationary phase in AYE broth and starved in freshwater for 2 hours and RNA was harvested with or without sublethal heat shock via immersion in a 55 degree C hot water bath for 5 minutes
2022-02-15 | GSE196713 | GEO