Table 1

P. aeruginosa mutants obtained by TnphoA mutagenesis

StrainGrowth in Arabidopsis leaves*Symptoms elicited in Arabidopsis% mouse mortalityGene identity
5 × 1035 × 105
PA145.5  ×  107Severe53100
33C7 8.3  ×  104None00Unknown§
1D7 7.5  ×  105Weak050 gacA
25A12 1.7  ×  106Weak1187Unknown
33A9 5.1  ×  106Moderate00Unknown
25F1 1.5  ×  104Moderate020Unknown
34H4 3.8  ×  106Moderate033Unknown
pho34B12 4.0  ×  106Moderate056Unknown
pho15 3.9  ×  104Moderate062 dsbA
16G12 2.3  ×  105Moderate20100Unknown
  • * Four different samples were taken using two leaf discs/sample. Control plants inoculated with 10 mM MgSO4 showed no symptoms during the course of the experiments. Three independent experiments gave similar results. 

  • Symptoms observed 4–5 days after infection. None, no symptoms; chlorosis, chlorosis circumscribing the inoculation site; weak, localized water-soaking and chlorosis of tissue circumscribing the inoculation site; moderate, moderate water-soaking and chlorosis with most of the tissue softened around the inoculation site; severe, severe soft-rotting of the entire leaf characterized by a water-soaked reaction zone and chlorosis around the inoculation site at 2–3 days postinfection. 

  • All animal experiments were conducted at least twice using 8–10 animals/experiment. Independent experiments showed similar percentage mortality rates. Mice were injected with ≈ 5 × 103 or 5 × 105 cells. 

  • § blastx analysis yielded no encoded proteins with significant homology.