FIGURE 5.

Intracellular oxidative stress was detected by dihydrorhodamine dye (5. 0 μg/ml) using flow cytometry under antibiotics: the wild-type, the fprB mutant strain (ΔfprB), and the fprB overexpressed strain (fprB OE) of P. putida (A, B, and C, respectively) and P. aeruginosa (D, E, and F, respectively). The concentrations of antibiotics were as follows: ampicillin (Amp, 150 μg/ml, red color), norfloxacin (Nor, 0.5 μg/ml, green color), and gentamicin (Gm, 5 μg/ml, blue color). A.U., absorbance unit.