The Phage shock protein (Psp) systems found in bacteria, archaea and higher plants respond to extracytoplasmic stresses that damage the cytoplasmic membrane and enable cells to repair their membranes. The conserved membrane-associated effector protein PspA has four alpha-helical domains (HD1-4) and as a high order oligomer helps to repair the membrane. In enterobacteria, under non-stress conditions PspA as a low order assembly directly inhibits its cognate transcription activator PspF. Here we show that N-terminal amphipathic helices ahA and ahB in PspA HD1 are functional determinants involved in negative gene control and stress signal-perception and its transduction via interactions with the PspBC membrane stress sensors and the IM. The amphipathic helices enable PspA to switch from a low order gene regulator into an inner membrane bound high order effector complex under membrane stress. Conserved residue proline 25 is involved in sequential use of the amphipathic helices and ahA-IM interaction. Single molecule imaging of eGFP-PspA and its amphipathic helices variants in live E. coli cells show distinct spatial and temporal organisations of PspA corresponding to its negative control and effector functions. These findings inform studies on the role of the Psp system in persister cell formation and cell envelope protection in bacterial pathogens and provide a basis for exploring the specialised roles of PspA homologues such as YjfJ, LiaH and VIPP1.