FIG. 1.

Spontaneous (No peroxide) and H₂O₂-induced Fos^r (150 μg/ml) mutant frequencies. (A) Mutant frequencies of strains PAO1 (white bars), PAO1 PA0355::ISlacZ/hah (black bars), and the complemented derivative PAO1 PA0355::ISlacZ/hah (pBBR-pfpI-01) (gray bars). (B) Frequencies of strains PA14 (white bars), the PA14-04650::MAR2xT7 mutant (black bars), and the complemented derivative PA14-04650 (pBBR-pfpI-14) (gray bars). In both panels, the viable cells remaining after peroxide treatment are shown below (the error bars indicate standard deviations). To compare the results adequately, the wild-type and mutant strains contained the appropriate empty vector without the wild-type gene.