Immunogold labeling of Hrp pili of Pseudomonas syringae pv. tomato assembled in minimal medium and in planta.

Journal Article (Journal Article)

Hypersensitive reaction and pathogenicity (hrp) genes are required for Pseudomonas syringae pv. tomato (Pst) DC3000 to cause disease in susceptible tomato and Arabidopsis thaliana plants and to elicit the hypersensitive response in resistant plants. The hrp genes encode a type III protein secretion system known as the Hrp system, which in Pst DC3000 secretes HrpA, HrpZ, HrpW, and AvrPto and assembles a surface appendage, named the Hrp pilus, in hrp-gene-inducing minimal medium. HrpA has been suggested to be the Hrp pilus structural protein on the basis of copurification and mutational analyses. In this study, we show that an antibody against HrpA efficiently labeled Hrp pili, whereas antibodies against HrpW and HrpZ did not. Immunogold labeling of bacteria-infected Arabidopsis thaliana leaf tissue with an Hrp pilus antibody revealed a characteristic lineup of gold particles around bacteria and/or at the bacterium-plant contact site. These results confirm that HrpA is the major structural protein of the Hrp pilus and provide evidence that Hrp pili are assembled in vitro and in planta.

Full Text

Duke Authors

Cited Authors

  • Hu, W; Yuan, J; Jin, QL; Hart, P; He, SY

Published Date

  • February 2001

Published In

Volume / Issue

  • 14 / 2

Start / End Page

  • 234 - 241

PubMed ID

  • 11204787

International Standard Serial Number (ISSN)

  • 0894-0282

Digital Object Identifier (DOI)

  • 10.1094/mpmi.2001.14.2.234


  • eng