Fig 4.
Acid resistance depends on the presence of rhamnose and arginine. Ty2, χ11548 (ΔaroD), and χ11568 (ΔaroD PrhaBAD adiAC) were grown to the stationary phase in EGA medium and then challenged with EG medium (pH 3.0). (A) Strains cultured in the presence or absence of 0.1% rhamnose. (B) Strains challenged in the presence or absence of 1 mM arginine. 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.