TABLE 3.
Identification and characteristics of a variety of mutants of Pseudomonas syringae strain B728a with altered biosurfactant production identified by using an atomized oil assay
| Locus of Tn5 insertion | Predicted function | No. of individual transposon hitsa | Avg surfactant halo radiusb (mm) ± SD | Drop collapsec | Avg swarming diamd (mm) ± SD | Avg SyfA expression (arbitrary units)e ± SD |
|---|---|---|---|---|---|---|
| WT (no insertion) | 8.7 ± 0.2 | Yes | 24.1 ± 0.5 | 1,716 ± 41 | ||
| Psyr_1233 (suhB) | Inositol monophosphatase | 1 | 5.0 ± 0.2 | No | 6.7 ± 0.2** | 110 ± 12** |
| Psyr_4094 (secA) | Protein secretion | 1 | 5.3 ± 0.5 | Yes | 12.5 ± 3.2** | 2,232 ± 116** |
| Psyr_2576 (syfA) | Syringafactin biosynthesis | 4 | 5.3 ± 0.3 | No | 10.8 ± 0.3** | NA |
| Psyr_2577 (syfB) | Syringafactin biosynthesis | 5 | 5.8 ± 0.4 | No | 10.17 ± 0.3** | NA |
| Psyr_4346 | Unknown | 1 | 6.0 ± 0.4 | Yes | 14.3 ± 0.7** | 900 ± 27** |
| Psyr_3619 | RNA processing and degradation | 3 | 6.2 ± 0.2 | No | 13.0 ± 0.6** | 53 ± 1** |
| Psyr_3958 (algT) | Alginate regulation | 1 | 11.0 ± 0.6 | Yes | 32.3 ± 0.8** | 2,691 ± 69** |
| Psyr_1407 (pmpR) | Virulence factor regulation | 1 | 12.0 ± 0.5 | No | 32.3 ± 3.8** | 87 ± 3** |
| Psyr_1747 (clpP) | Posttranslational modification | 1 | 12.3 ± 0.4 | Yes | 19.3 ± 0.7** | 626 ± 64** |
| Psyr_3957 (mucA)f | Alginate regulation | 1 | 12.3 ± 0.4 | Yes | 20.3 ± 1.4** | 2,378 ± 63** |
| Psyr_1748 (clpX) | Posttranslational modification | 5 | 12.2 ± 0.9 | Yes | 21.5 ± 1.3* | 1,595 ± 54 |
| Psyr_1350 (rseP) | Alginate regulation | 4 | 12.7 ± 0.3 | Yes | 32.8 ± 1.7** | 2,655 ± 71** |
Number of times that independent mutants were identified as insertions in the same gene.
Halos with significantly smaller or larger radii than those of the WT (P < 0.01 for all by t test).
Ability to cause drop collapse of a water droplet on an oil surface.
Bacterial motility over semisolid agar plates. Motility was significantly different from that of the wild type at a P value of <0.05 (*) or a P value of <0.01 (**), as determined by a t test.
Arbitrary units of relative fluorescence of the PsyfA-gfp reporter in mutant strains. Expression was significantly different from that of the wild type at a P value of <0.01 (**), as determined by a t test.
The original mutant strain had a decreased halo size. This strain saved for testing most likely possesses a secondary mutation that has reversed the phenotype of the original mutation.