FIG 3.

Deletion of arc genes disrupt ability to utilize arginine and citrulline for protection against acid stress. Wild-type bacteria and the indicated strains were cultured in unsupplemented THY medium (Unsupp.), THY medium plus 10 mM arginine, or THY medium plus 10 mM citrulline for a 6-day period. At the indicated times, the cultures were resuspended, and a small aliquot was removed and serially diluted in PBS, followed by plating on solid medium for enumeration. The data displayed are the mean of the recovered CFU from at least three independent experiments.