Figure 3.

Flagellar-gene promoter activities in wild-type and flrA-mutant strains. Promoters for 11 genes were transcriptionally fused to lacZ as described in Experimental Procedures, and β-galactosidase activity was measured in wild type and the flrA::Tnerm mutant after growth in seawater-based tryptone (SWT) to an OD₆₀₀ of ∼0.5. Note that not all promoters (e.g., flgA) are controlled by FlrA. Asterisks indicate both a significance difference at P ≤ 0.05 using a Student's t-test and a fold change ≥2.