TABLE 2.
Growth rates in MOPS minimal medium
| Strain/isolate | Doubling time (min)ab | Strain | lasR | Interaction |
|---|---|---|---|---|
| PA14 | 62.5 (2.0) | |||
| PA14 ΔlasR | 61.4 (2.9) | |||
| fusA1 G61A | 66.3 (2.9) | P < 0.0005 | P < 0.01 | P < 0.005 |
| fusA1 G61A ΔlasR | 78.2 (2.2)***c | F = 49.91 | F = 13.81 | F = 19.73 |
| T1 | 67.7 (4.0) | P < 0.0005 | P < 0.02 | P < 0.005 |
| T1 ΔlasR | 79.7 (2.5)*** | F = 47.61 | F = 10.41 | F = 14.81 |
| T3 | 74.9 (3.4) | P < 0.0001 | ns | P < 0.04 |
| T3 ΔlasR | 83.0 (3.5)* | F = 96.27 | F = 4.084 | F = 6.930 |
The values represent the average doubling time during logarithmic growth determined from three independent experiments, with the standard deviation indicated in parentheses. Standard deviation was zero where not indicated.
The significance of the effects of strain (PA14, fusA1 G61A, T1, or T3) and lasR allele (intact lasR or ΔlasR) and the interaction of the two on MIC was determined by two-way ANOVA by performing pairwise comparisons of each LasR+/− strain pair with that of PA14. The interaction was significant in all cases. For fusA1 G61A, P < 0.005 and F = 19.73; for T1, P < 0.005 and F = 14.81; for T3, P < 0.04 and F = 6.930.
Asterisks indicate the significance of comparing LasR+ and LasR− of each strain using Sidak’s post hoc analysis with P values adjusted for multiple comparisons of all strains. There was no significance (P > 0.05) unless indicated. *, P < 0.05; ***, P < 0.001.