Fig 5.
Acid resistance of a ΔaroD1299 mutant containing rhamnose-regulated arginine decarboxylase at pH 2.5. Ty2, χ11500 (ΔadiA-adiC), χ11548 (ΔaroD), and χ11568 (ΔaroD PrhaBAD adiAC) were grown to the stationary phase in EGA medium containing 0.1% rhamnose and then challenged with EG medium containing 1 mM arginine at pH 2.5 for 1 h. Survival in all assays was monitored by plating on LB agar containing all necessary supplements. The data shown are the means and SEM from three independent assays. Pairs of data marked with an asterisk are significantly different (P < 0.05).