Proteome profiling of Pseudomonas aeruginosa PAO1 identifies novel responders to copper stress

BACKGROUND: The opportunistic pathogen, Pseudomonas aeruginosa is well known for its environmental and metabolic versatility, yet many of the functions of its gene-products remain to be fully elucidated. This study's objective was to illuminate the potential functions of under-described gene-products during the medically relevant copper-stress condition.

RESULTS: We used data-independent acquisition mass spectrometry to quantitate protein expression changes associated with copper stress in P. aeruginosa PAO1. Approximately 2000 non-redundant proteins were quantified, with 78 proteins altering in abundance by +/- 1.5-fold or more when cultured to mid-log growth in the presence of 50 μM copper sulfate. One-third of those differentially expressed proteins have no prior established functional roles.

CONCLUSIONS: This study provides evidence for the functional involvement of some specific proteins in enabling P. aeruginosa to survive under sub-lethal concentrations of copper. This further paves the way for targeted investigations into the specific mechanisms of their activity.