Proteomic profiling of the Pseudomonas aeruginosa stringent response highlights global adaptive responses during stationary phase.

Proteomic profiling reveals that the (p)ppGpp-mediated stringent response in Pseudomonas aeruginosa regulates over 339 proteins during stationary phase, highlighting extensive metabolic shutdown and stress adaptation.

• Why it matters: Understanding how P. aeruginosa adapts to stress and transitions into stationary phase is crucial for developing strategies against its pathogenicity, yet protein-level processes under stringent response control remain poorly characterized.
• What they did: Researchers performed shotgun proteomic profiling (LC-MS/MS) on a (p)ppGpp-null ΔSR mutant and its wild-type during late exponential and stationary phases, identifying 146 differentially abundant proteins in late exponential and 339 in stationary phase.
• The result: The study shows (p)ppGpp is key in shutting down metabolic processes and activating stress responses, with findings suggesting additional post-transcriptional regulation involving small RNAs, which may influence P. aeruginosa's stress resilience.