TABLE 3.
Effects of plasmids that carry the lasI or rhlI gene or both the lasI and rhlI genes on the virulence of P. aeruginosa JP2
| Strain | No. of mice dead/total (% mortality)a
|
Avg % mortalityb | ||
|---|---|---|---|---|
| Expt 1 | Expt 2 | Expt 3 | ||
| PAO1 | 7/7 (100) | 5/6 (83.3) | 6/6 (100) | 94.3 |
| JP2/pSW200c | 0/5 (0) | 1/5 (20) | 0/5 (0) | 6.7 |
| JP2/pLASI-2c | 4/5 (80) | 3/5 (60) | 4/5 (80) | 73.3 |
| JP2/pJPP45c | 2/5 (40) | 3/5 (60) | 2/5 (40) | 46.7 |
| JP2/pJPP42c | 4/5 (80) | 5/5 (100) | 5/5 (100) | 93.3 |
A total of 2 × 102 to 3 × 102 CFU of each strain was injected subcutaneously at the burn site immediately after burning. The mice were burned and then inoculated with each strain as described in Materials and Methods. The mortality among mice infected with each strain was determined at 48 h post burn infection as previously described (34). Three separate experiments were conducted with each strain.
The average percent mortality of three independent experiments is shown.
Plasmid pSW200 is a cloning vector (negative control), plasmid pLASI-2 carries a DNA fragment containing the intact lasI gene, plasmid pJPP45 carries a DNA fragment containing the intact rhlI gene, and plasmid pJPP42 carries a DNA fragment containing the intact lasI and rhlI genes.