Stationary-phase, acid-tolerant (A), acid-sensitive (B), and acid-resistant (C) <i>E. coli</i> O157:H7 in 10% CB suspension (pH 3.1) and low-pH buffer (pH 3.1).

<p>Stationary-phase cells were grown overnight in LB media. Data are presented as the mean ± standard deviation (SD) for three independent experiments. The dotted line represents the limit of detection.