FIG. 1.

Growth deficiency of ΔfupA/B mutants under conditions of iron limitation. (A) Growth on iron-replete (MHA) and iron-limiting (CDM-Fe) agar plates. LVS and the mutants were grown in CDM, and serially diluted cultures were spotted on iron-replete and iron-limiting plates in parallel. (B) Growth in liquid medium. Washed cells were inoculated in iron-replete and iron-limiting che-CDM, and growth was followed over a period of 48 h. Cultures were grown in triplicate, and means and standard deviations of data representing the results of one representative experiment are shown in the growth plot. The strains used were LVS, GR13 (LVS ΔfslE), GR16 (LVS ΔfupA/B), and GR17 (LVS ΔfslE ΔfupA/B).