Proteomic analysis of the adaptive responses of Pseudomonas aeruginosa to aminoglycoside antibiotics.

The opportunistic human pathogen, Pseudomonas aeruginosa, is a major cause of life-threatening infections in patients with cystic fibrosis. These infections are usually controlled through antibiotic intervention. In this study we use quantitative proteomic analysis to investigate how P. aeruginosa adapts to the presence of sub-lethal concentrations of two front-line, clinically-relevant aminoglycosides that are often used to treat P. aeruginosa infections; tobramycin and gentamicin. We found that aminoglycosides caused the oxidative steps of the citric acid cycle to be partially bypassed and also led to down-regulation of proteins involved in iron uptake. This may be a means of reducing aminoglycoside-induced oxidative stress in the cells, and this is discussed.