Growth of E . coli JA300, JA300 acrR IS marR , and CH7 in LBGMg liquid medium in the absence of an organic solvent (A) and in the presence of n -hexane (B) and cyclohexane (C). A 100-μl culture of overnight-grown E. coli strain was inoculated to 10 ml of fresh LBGMg liquid medium overlaid with an organic solvent. This two-phase culture was incubated at 30°C. Growth was monitored by measuring turbidity (OD660). Values indicate means of results and standard deviations of results from three independent experiments. Symbols: (△) JA300; (·) JA300 acrR IS marR; (○) CH7.