Identification of the alternative sigma factor SigX regulon and its implications for Pseudomonas aeruginosa pathogenicity.
dc.contributor.author | Blanka, Andrea | |
dc.contributor.author | Schulz, Sebastian | |
dc.contributor.author | Eckweiler, Denitsa | |
dc.contributor.author | Franke, Raimo | |
dc.contributor.author | Bielecka, Agata | |
dc.contributor.author | Nicolai, Tanja | |
dc.contributor.author | Casilag, Fiordiligie | |
dc.contributor.author | Düvel, Juliane | |
dc.contributor.author | Abraham, Wolf-Rainer | |
dc.contributor.author | Kaever, Volkhard | |
dc.contributor.author | Häussler, Susanne | |
dc.date.accessioned | 2015-01-16T15:07:52Z | |
dc.date.available | 2015-01-16T15:07:52Z | |
dc.date.issued | 2014-01 | |
dc.identifier.citation | Identification of the alternative sigma factor SigX regulon and its implications for Pseudomonas aeruginosa pathogenicity. 2014, 196 (2):345-56 J. Bacteriol. | en |
dc.identifier.issn | 1098-5530 | |
dc.identifier.pmid | 24187091 | |
dc.identifier.doi | 10.1128/JB.01034-13 | |
dc.identifier.uri | http://hdl.handle.net/10033/338491 | |
dc.description.abstract | Pseudomonas aeruginosa is distinguished by its broad metabolic diversity and its remarkable capability for adaptation, which relies on a large collection of transcriptional regulators and alternative sigma (σ) factors. The largest group of alternative σ factors is that of the extracytoplasmic function (ECF) σ factors, which control key transduction pathways for maintenance of envelope homeostasis in response to external stress and cell growth. In addition, there are specific roles of alternative σ factors in regulating the expression of virulence and virulence-associated genes. Here, we analyzed a deletion mutant of the ECF σ factor SigX and applied mRNA profiling to define the SigX-dependent regulon in P. aeruginosa in response to low-osmolarity-medium conditions. Furthermore, the combination of transcriptional data with chromatin immunoprecipitation (ChIP) followed by high-throughput sequencing (ChIP-seq) led to the identification of the DNA binding motif of SigX. Genome-wide mapping of SigX-binding regions revealed enrichment of downstream genes involved in fatty acid biosynthesis, type III secretion, swarming and cyclic di-GMP (c-di-GMP) signaling. In accordance, a sigX deletion mutant exhibited altered fatty acid composition of the cell membrane, reduced cytotoxicity, impaired swarming activity, elevated c-di-GMP levels, and increased biofilm formation. In conclusion, a combination of ChIP-seq with transcriptional profiling and bioinformatic approaches to define consensus DNA binding sequences proved to be effective for the elucidation of the regulon of the alternative σ factor SigX, revealing its role in complex virulence-associated phenotypes in P. aeruginosa. | |
dc.language.iso | en | en |
dc.relation | info:eu-repo/grantAgreement/EC/FP7/260276/ | en |
dc.rights | openAccess | en |
dc.subject.mesh | Binding Sites | en |
dc.subject.mesh | Chromatin Immunoprecipitation | en |
dc.subject.mesh | Culture Media | en |
dc.subject.mesh | Gene Deletion | en |
dc.subject.mesh | Gene Expression Profiling | en |
dc.subject.mesh | Gene Expression Regulation, Bacterial | en |
dc.subject.mesh | High-Throughput Nucleotide Sequencing | en |
dc.subject.mesh | Osmotic Pressure | en |
dc.subject.mesh | Protein Binding | en |
dc.subject.mesh | Pseudomonas aeruginosa | en |
dc.subject.mesh | Regulon | en |
dc.subject.mesh | Sigma Factor | en |
dc.subject.mesh | Virulence Factors | en |
dc.title | Identification of the alternative sigma factor SigX regulon and its implications for Pseudomonas aeruginosa pathogenicity. | en |
dc.type | Article | en |
dc.contributor.department | Helmholtz Centre of infection research; Inhoffenstr. 7; D38124 Braunschweig; Germany. | en |
dc.identifier.journal | Journal of bacteriology | en |
refterms.dateFOA | 2018-06-13T05:35:17Z | |
html.description.abstract | Pseudomonas aeruginosa is distinguished by its broad metabolic diversity and its remarkable capability for adaptation, which relies on a large collection of transcriptional regulators and alternative sigma (σ) factors. The largest group of alternative σ factors is that of the extracytoplasmic function (ECF) σ factors, which control key transduction pathways for maintenance of envelope homeostasis in response to external stress and cell growth. In addition, there are specific roles of alternative σ factors in regulating the expression of virulence and virulence-associated genes. Here, we analyzed a deletion mutant of the ECF σ factor SigX and applied mRNA profiling to define the SigX-dependent regulon in P. aeruginosa in response to low-osmolarity-medium conditions. Furthermore, the combination of transcriptional data with chromatin immunoprecipitation (ChIP) followed by high-throughput sequencing (ChIP-seq) led to the identification of the DNA binding motif of SigX. Genome-wide mapping of SigX-binding regions revealed enrichment of downstream genes involved in fatty acid biosynthesis, type III secretion, swarming and cyclic di-GMP (c-di-GMP) signaling. In accordance, a sigX deletion mutant exhibited altered fatty acid composition of the cell membrane, reduced cytotoxicity, impaired swarming activity, elevated c-di-GMP levels, and increased biofilm formation. In conclusion, a combination of ChIP-seq with transcriptional profiling and bioinformatic approaches to define consensus DNA binding sequences proved to be effective for the elucidation of the regulon of the alternative σ factor SigX, revealing its role in complex virulence-associated phenotypes in P. aeruginosa. |