The Type III Secretion Systems of Plant-Associated Pseudomonads: Genes and Proteins on the Move

  • Gail M. Preston
  • Alan Collmer


Pseudomonas syringae and Pseudomonas fluorescens are plant-associated bacteria that have very different relationsh ips with plants. P. syringae is a foliar pathogen that affects a wide range of crop plants, whereas P. fluorescens is a commensal that colonizes the rhizosphere and can even benefit plants as a plant growth-promoting rhizobacterium (PGPR). The type III secretion system (TTSS), which is capable of injecting virulence effector proteins into plant cells, is central to the pathogenicity of P. syringae and is also present in some strains of P. fluorescens. The TTSS is thus a logical entry point for exploring the diversity and evolution of plant-associated pseudomonads and the molecular basis for their differing interactions with plants.


Secretion System Effector Gene Yersinia Enterocolitica Xanthomonas Campestris Tomato DC3000 
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Copyright information

© Springer Science+Business Media New York 2004

Authors and Affiliations

  • Gail M. Preston
    • 1
  • Alan Collmer
    • 2
  1. 1.Department of Plant SciencesUniversity of OxfordOxfordUK
  2. 2.Department of Plant PathologyCornell UniversityIthacaUSA

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