PilJ localizes to cell poles and is required for type IV pilus extension in Pseudomonas aeruginosa

Curr Microbiol. 2007 Nov;55(5):389-95. doi: 10.1007/s00284-007-9008-5. Epub 2007 Aug 23.


Twitching motility allows Pseudomonas aeruginosa to respond to stimuli by extending and retracting its type IV pili (TFP). PilJ is a protein necessary for this surface-associated twitching motility and bears high sequence identity with Escherichia coli methyl-accepting chemotaxis proteins (MCP). Here, we report that whereas wild-type P. aeruginosa PAO1 cells have extended pili at a single pole, pilJ mutant cells have shortened pili often at both poles despite normal levels of pilin accumulation, suggesting that PilJ is required for full TFP assembly/extension. Using yellow fluorescent protein fusions (pilJ-yfp), both plasmid born and in-frame chromosomal constructs, we determined that PilJ localizes to both poles of the cell. Overexpression of pilJ-yfp resulted in the protein accumulating between the poles.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Bacterial Proteins / physiology
  • Blotting, Western
  • Fimbriae Proteins / genetics
  • Fimbriae Proteins / metabolism*
  • Fimbriae Proteins / physiology
  • Fimbriae, Bacterial / metabolism*
  • Fimbriae, Bacterial / physiology
  • Luminescent Proteins / genetics
  • Luminescent Proteins / metabolism
  • Microscopy, Fluorescence
  • Mutation
  • Pseudomonas aeruginosa / genetics
  • Pseudomonas aeruginosa / metabolism*
  • Pseudomonas aeruginosa / physiology
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism


  • Bacterial Proteins
  • Luminescent Proteins
  • Recombinant Fusion Proteins
  • pilJ protein, Pseudomonas aeruginosa
  • yellow fluorescent protein, Bacteria
  • Fimbriae Proteins