Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2003-11-17
pubmed:abstractText
The single polar flagellum of Pseudomonas aeruginosa is an important virulence and colonization factor of this opportunistic pathogen. In this study, the annotation of the genes belonging to the fla regulon was updated and their organization was analysed in strains PAK and PAO1, representative type-a and type-b strains of P. aeruginosa respectively. The flagellar genes are clustered in three non-contiguous regions of the chromosome. A polymorphic locus flanked by flgJ and fleQ in Region I contains a glycosylation island in PAK. The expression and ordered assembly of the complex multicomponent flagellum is intricately regulated. Dedicated flagellar genes fleQ, fleS, fleR, fliA, flgM and fleN encode proteins that participate in the regulation of the flagellar transcriptional circuit. In addition, expression of the flagellum is coordinately regulated with other P. aeruginosa virulence factors by the alternative sigma factor sigma54, encoded by rpoN. In order to gain insight into the hierarchical regulation of flagellar genes, deletion mutations were constructed in fleQ, fleR, fliA and rpoN. The transcriptional impact of these mutations was examined by transcriptional profiling using a P. aeruginosa whole genome microarray. Analysis of the transcriptomes generated for each of these mutants indicates a four-tiered (Classes I-IV) hierarchy of transcriptional regulation. Class I genes are constitutively expressed and include the transcriptional regulator fleQ and the alternative sigma factor fliA (sigma28). Class II genes including fleSR, encoding a two-component regulatory system require FleQ and RpoN (sigma54) for their transcriptional activation. Class III genes are positively regulated by the activated response regulator FleR in concert with RpoN. The transcription of Class IV genes is dependent on the availability of free FliA following the export of the FliA specific antisigma factor FlgM through the basal body rod-hook structure (assembled from Class II and III gene products). Two previously uncharacterized genes, which are coordinately regulated with known flagellar genes have been identified by genome-wide analysis and their role in flagellar biogenesis was analysed.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0950-382X
pubmed:author
pubmed:issnType
Print
pubmed:volume
50
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
809-24
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:14617143-Bacterial Proteins, pubmed-meshheading:14617143-Base Sequence, pubmed-meshheading:14617143-DNA-Binding Proteins, pubmed-meshheading:14617143-DNA-Directed RNA Polymerases, pubmed-meshheading:14617143-Flagella, pubmed-meshheading:14617143-Gene Expression Profiling, pubmed-meshheading:14617143-Gene Expression Regulation, Bacterial, pubmed-meshheading:14617143-Gene Order, pubmed-meshheading:14617143-Genes, Bacterial, pubmed-meshheading:14617143-Molecular Sequence Data, pubmed-meshheading:14617143-Pseudomonas aeruginosa, pubmed-meshheading:14617143-RNA Polymerase Sigma 54, pubmed-meshheading:14617143-Regulon, pubmed-meshheading:14617143-Sigma Factor, pubmed-meshheading:14617143-Trans-Activators, pubmed-meshheading:14617143-Transcription, Genetic, pubmed-meshheading:14617143-Transcription Factors
pubmed:year
2003
pubmed:articleTitle
A four-tiered transcriptional regulatory circuit controls flagellar biogenesis in Pseudomonas aeruginosa.
pubmed:affiliation
Department of Medicine/Infectious Diseases, University of Florida, Gainesville, FL 32610, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't