Fig. 1
The roles of fecA, fciTABC operon, Smlt2356, and feoABI operon in ferric citrate acquisition in an iron-depleted condition. The logarithmic-phase bacterial cells of 2 × 105 CFU/μl were tenfold serially diluted. Five microliters of bacterial suspension were spotted onto the LB agar plates as indicated. The concentrations of DIP, ferric citrate, FeSO4, and ascorbic acid used were 50 μg/ml, 110 μM, 70 μM, and 80 μM, respectively. The growth of bacterial cells was recorded after 24-h incubation at 37 °C. A Role of fecA and fciTABC operon in ferric citrate acquisition in an iron-depleted condition. B Roles of Smlt2356 and feoABI operon in the acquisition of ferric citrate and ferrous iron in an iron-depleted condition