Figure 2

Quantitative assay of intracellular reactive oxygen species under different n-butanol concentrations. The OD₆₀₀ values of engineered E. coli strains were measured in cells cultured in PYG medium with different concentrations of n-butanol (vol/vol) at 37°C TBHP represents the positive control of the strains cultured with 0% n-butanol, but treated with TBHP (a known stressor that produces intracellular H₂O₂). Values are averages of three replicate experiments.