Fig. 3

Colistin exposure protection to P. aeruginosa provided by Cdp-producing S. maltophilia strains during cocultures. a Planktonic coculture assay. Changes in viable cell number were estimated for P. aeruginosa strain PAO1 (red) and S. maltophilia strains (black). The concentration of residual colistin in cocultures was measured after colistin spike (32 mg/L). b Solid agar coculture assay. The bacterial lawn of S. maltophilia strains was positioned at the bottom. Red arrows indicate the spreading growth of P. aeruginosa strain PAO1 toward S. maltophilia strains