FIG 3.

ESKAPE pathogens evolve rapidly toward high persister levels under in vitro intermittent aminoglycoside therapy. The antibiotics used were amikacin (Gram-negative pathogens) (a) or gentamicin (Gram-positive pathogens) (b) at 400 μg/ml for 5 h. Each cycle consisted of (i) antibiotic killing for 5 h, (ii) removal of the antibiotic and transfer to fresh medium, and (iii) batch growth to stationary phase. Cycles were repeated every 24 h (S. aureus, E. aerogenes, and E. faecium) or 48 h (P. aeruginosa, A. baumannii, and K. pneumoniae). Two independent replicates per species are shown.