Co-ordination of pathogenicity island expression by the BipA GTPase in enteropathogenic Escherichia coli (EPEC)

Mol Microbiol. 2003 Apr;48(2):507-21. doi: 10.1046/j.1365-2958.2003.t01-1-03447.x.


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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adhesins, Bacterial / metabolism
  • Carrier Proteins / metabolism
  • Escherichia coli / genetics
  • Escherichia coli / metabolism*
  • Escherichia coli / pathogenicity
  • Escherichia coli Proteins / genetics
  • Escherichia coli Proteins / metabolism*
  • Flagella / metabolism
  • GTP Phosphohydrolases / genetics
  • GTP Phosphohydrolases / metabolism*
  • Gene Expression Regulation, Bacterial*
  • HeLa Cells / metabolism
  • HeLa Cells / ultrastructure
  • Humans
  • Operon
  • Phosphoproteins / genetics
  • Phosphoproteins / metabolism*
  • Temperature
  • Trans-Activators / metabolism
  • Transcription, Genetic
  • Virulence Factors / metabolism*


  • Adhesins, Bacterial
  • Carrier Proteins
  • Escherichia coli Proteins
  • Ler protein, E coli
  • Phosphoproteins
  • Trans-Activators
  • Virulence Factors
  • eaeA protein, E coli
  • GTP Phosphohydrolases
  • typA protein, E coli