THE ROLES THAT DIFFERENT PILI CLASSES IN XYLELLA FASTIDIOSA PLAY IN COLONIZATION OF GRAPEVINES AND PIERCES DISEASE PATHOGENESIS

• Author(s): Burr, Thomas; Cursino, Luciana; Hoch, Harvey;
• Abstract: Type I and type IV pili of Xylella fastidiosa play different roles in twitching motility, biofilm formation, and cell-cell aggregation. Thirty twitching mutants were generated with an EZ::TN transposome system and type IV pilus-associated genes were identified, including fimT, pilX, pilY1, pilO, and pilR. Mutations in all resulted in a twitch-minus phenotype except that pilY1 mutant was twitching-reduced. A fimA mutant lacked type I pili and altered biofilm development and twitching. A fimA/pilO double mutant lacked both classes of pili, was twitch-minus and produced almost no visible biofilm. The gene for the type IV pilin (pilA), was cloned and expressed (predicted 15 KDa protein). The pilin sequence is 38% and 55% identical to that of the type IV pilin from Pseudomonas aeruginosa and P. syringae pv. tomato, respectively. A monoclonal antibody against the pilA gene product (prepilin) is being prepared.
• Publication Date: Nov 2006
• Journal: 2006 Pierce's Disease Research Symposium