Submitted to: APS Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 5/20/2004
Publication Date: 7/20/2004
Citation: Mavrodi, O.V., Mavrodi, D.V., Weller, D.M., Thomashow, L.S. 2004. Role of sss recombinase and dsba in root colonization by pseudomonas fluorescens Q8r1-96. APS Annual Meeting. Phytopathology 94: S67.
Technical Abstract: The 2,4-diacetylpholorglucinol (DAPG)-producing strain Pseudomonas fluorescens Q8r1-96 suppresses numerous soilborne pathogens and aggressively colonizes the roots of wheat and pea. Clones containing two genes, sss recombinase and dsbA, encoding a site-specific recombinase and a periplasmic disulfide bond-forming protein, respectively, were identified by PCR in a Q8r1-96 genomic library, sequenced, and used to construct gene replacement mutants in Q8r1-96. Colonies formed by the sss mutant did not differ from those of Q8r1-96, whereas those of the dsbA mutant exhibited altered colony morphology, reduced fluorescence and decreased motility. Both mutants produced DAPG and inhibited Gaeumannomyces graminis var. tritici in vitro. The mutants are being assessed in greenhouse studies for their ability to colonize and persist in the rhizosphere of wheat.