FIG 4.

Benzoate-evolved strain G5-2 outgrows ancestor W3110 in the presence of benzoate but grows poorly in benzoate with chloramphenicol. The growth medium was LBK with (A) 100 mM PIPES and 20 mM benzoate (pH 6.5), (B) 100 mM MOPS, 5 mM benzoate (pH 7.0), and 8 μg/ml chloramphenicol (CHL), or (C) 100 mM MOPS (pH 7.0) and 4 μg/ml CHL. For each strain, 8 replicate curves from microplate wells are shown. For strains G5-2 and W3110 in each panel, cell density values post-log phase (OD₆₀₀ at 16 h) were ranked and compared by using the Friedman test; post hoc Conover pairwise comparisons were conducted with Holm-Bonferroni-adjusted P values.