title: Co-ordination of pathogenicity island expression by the BipA GTPase in enteropathogenic Escherichia coli (EPEC).
abstract: BipA is a novel member of the ribosome binding GTPase superfamily and is widely distributed in bacteria and plants. We report here that it regulates -multiple cell surface- and virulence-associated -components in the enteropathogenic Escherichia coli (EPEC) strain E2348/69. The regulated components include bacterial flagella, the espC pathogenicity island and a type III secretion system specified by the locus of enterocyte effacement (LEE). BipA positively regulated the espC and LEE gene clusters through transcriptional control of the LEE-encoded regulator, Ler. Additionally, it affected the pattern of proteolysis of intimin, a key LEE-encoded adhesin specified by the LEE. BipA control of the LEE operated independently of the previously characterized regulators Per, integration host factor and H-NS. In contrast, it negatively regulated the flagella-mediated motility of EPEC and in a Ler-independent manner. Our results indicate that the BipA GTPase functions high up in diverse regulatory cascades to co-ordinate the expression of key pathogenicity islands and other virulence-associated factors in E. coli.
authors.affiliation: Division of Biochemistry and Molecular Biology, School of Biological Sciences, University of Southampton, Bassett Crescent East, Southampton SO16 7PX, UK.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Grant
authors.forename: Michele
authors.initials: M
authors.lastname: Farris
authors.forename: Peter
authors.initials: P
authors.lastname: Alefounder
authors.forename: Peter H
authors.initials: PH
authors.lastname: Williams
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Woodward
authors.forename: C David
authors.initials: CD
authors.lastname: O'Connor
mesh_terms: D018829:Adhesins, Bacterial / Q000378:metabolism; D002352:Carrier Proteins / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism*; D005407:Flagella / Q000378:metabolism; D020558:GTP Phosphohydrolases / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D006367:HeLa Cells / Q000378:metabolism / Q000648:ultrastructure; D006801:Humans; D009876:Operon; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism*; D013696:Temperature; D015534:Trans-Activators / Q000378:metabolism; D014158:Transcription, Genetic; D037521:Virulence Factors / Q000378:metabolism*
chemical_list: D018829:Adhesins, Bacterial; D002352:Carrier Proteins; D029968:Escherichia coli Proteins; C465556:Ler protein, E coli; D010750:Phosphoproteins; D015534:Trans-Activators; D037521:Virulence Factors; C073819:eaeA protein, E coli; D020558:GTP Phosphohydrolases; C408370:typA protein, E coli