Acid resistance of <i>E. coli</i> K-12 and EHEC.

<p>Cells were grown in LB glucose with 1 µM oxo-C6 or 0.1% EA at either 37°C or 30°C and then subcultured into pre-warmed MEM with glucose and glutamate at pH 2.0 with continued incubation at the same temperature. Resistance to the acid challenge was determined by plating for cfu/ml every hour for two hours. <i>E. coli</i> K-12 wild-type MG1655 and <i>sdiA</i> mutant JNS21 at 37°C (A) and 30°C (B). EHEC wild-type 700927 and <i>sdiA</i> mutant DL1 at 37°C (C) and 30°C (D). Each strain was assayed in triplicate and error bars represent standard deviation.