Relative fluorescence of ∆ zmsA (p P desAB -Gfp) and its variants with in-frame deletion of dzrR or the five canonical ESR genes in the presence of envelope-targeting antimicrobial agents. The relative fluorescence was expressed as the fluorescence of bacterial cells treated with antimicrobial agents normalized to the fluorescence of bacterial cells treated with the same amount of solvent (DMSO or methanol). The relative fluorescence is presented as mean ± SE, n = 3. Statistical analysis was performed using a two-tailed unpaired Student’s t test versus the solvent control. ** P < 0.01. In A and B , bacterial cell cultures at an optical density at 600 nm (OD 600 ) about 0.5 were treated with different chemical compounds at 28 °C for 8 h. After incubation, the average fluorescence intensity of 50,000 bacterial cells was measured by a CytoFLEX flow cytometer (Beckman Coulter, Brea, CA, USA) for determining the relative fluorescence of bacterial strains under different treatments. The final concentration of the chemical compounds were 50 μg/ml ( A ) or 10 μg/ml ( B ), respectively, except for chlorhexidine, which was added at 2 μg/ml as a higher concentration of chlorhexidine arrested the growth of D. oryzae EC1
