Fig. 2

LeuA E108K substitution causes leucine auxotrophy in P. aeruginosa. PAO1161 leuA allele, carrying the mutation, was replaced with the PAO1 allele to yield strain PAO1161 PA3792⁺ (leu+). Growth of PAO1161 (leu-) and PAO1161 PA3792⁺ (leu+) strains on solid (a) and liquid (b) minimal medium containing 0.25% citrate with or without 10 μg ml^− 1 leucine. Data represent mean OD_600nm ± SD for 6 biological replicates