Ralstonia solanacearum produces hrp-dependent pili that are required for PopA secretion but not for attachment of bacteria to plant cells.
As in many other Gram-negative plant pathogenic bacteria, the Ralstonia solanacearum hrp genes are involved in the production of a type III secretion apparatus that allows the translocation of PopA protein to the external medium. Here, we show that hrp genes are also involved in the biogenesis of pili that are mainly composed of the HrpY protein. These pili are produced at one pole of the bacterium and are also released into the external medium where they can form very long straight bundles. An hrpY mutant is defective in pilus production, impaired in interactions with plants and in secretion of the PopA protein but not in attachment to plant cells.
Van Gijsegem
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Laboratoire de Biologie Moléculaire des Relations Plantes-Microorganismes, INRA-CNRS, chemin de Borde Rouge, BP27 31326 Castanet Tolosan Cedex, France. frgij@gengenp.rug.ac.be
Vasse
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Camus
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Marenda
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Boucher
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D000595:Amino Acid Sequence; D001422:Bacterial Adhesion; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D020562:Betaproteobacteria / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D010861:Fimbriae, Bacterial / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D019084:Fluorescent Antibody Technique, Indirect; D015964:Gene Expression Regulation, Bacterial; D008854:Microscopy, Electron; D008857:Microscopy, Interference; D008969:Molecular Sequence Data; D005810:Multigene Family; D010935:Plant Diseases / Q000382:microbiology*; D010944:Plants / Q000382:microbiology*; D020539:Sequence Analysis, Protein; D013997:Time Factors
D001426:Bacterial Proteins