A four-tiered transcriptional regulatory circuit controls flagellar biogenesis in Pseudomonas aeruginosa.

摘要: The single polar flagellum of Pseudomonas aeruginosa is an important virulence and colonization factor this opportunistic pathogen. In study, the annotation genes belonging to fla regulon was updated their organization analysed in strains PAK PAO1, representative type-a type-b P. respectively. flagellar are clustered three non-contiguous regions chromosome. A polymorphic locus flanked by flgJ fleQ Region I contains a glycosylation island PAK. expression ordered assembly complex multicomponent intricately regulated. Dedicated fleQ, fleS, fleR, fliA, flgM fleN encode proteins that participate regulation transcriptional circuit. addition, coordinately regulated with other factors alternative sigma sigma54, encoded rpoN. order gain insight into hierarchical genes, deletion mutations were constructed fliA impact these examined profiling using whole genome microarray. Analysis transcriptomes generated for each mutants indicates four-tiered (Classes I-IV) hierarchy regulation. Class constitutively expressed include regulator (sigma28). II including fleSR, encoding two-component regulatory system require FleQ RpoN (sigma54) activation. III positively activated response FleR concert RpoN. transcription IV dependent on availability free FliA following export specific antisigma FlgM through basal body rod-hook structure (assembled from gene products). Two previously uncharacterized which known have been identified genome-wide analysis role biogenesis analysed.