Positively regulates the expression of about fifteen genes involved in acid resistance such as gadA, gadB and gadC. Depending on the conditions (growth phase and medium), can repress gadW (By similarity). Negatively regulates perA expression in acidic conditions and positively regulates it in alkaline conditions. Homodimer. Expression can be activated by RpoS and repressed by CRP, H-NS and GadW, depending on the conditions.