A Low pH-Inducible, PhoPQ-Dependent Acid Tolerance Response Protects Salmonella typhimurium against Inorganic Acid Stress

The acid tolerance response enables Salmonella typhimurium to survive exposures to potentially lethal acidic environments. The acid stress imposed in a typical assay for acid tolerance (log-phase cells in minimal glucose medium) was shown to comprise both inorganic (i.e., low pH) and organic acid components. A gene previously determined to affect acid tolerance, atbR , was identified as pgi , the gene encoding phosphoglucoisomerase. Mutations in...