Figure 4.
Time-dependent uptake of 55Fe-14C-lysineCAM siderophore analog into cells of A. hydrophila. Conditions were as described in Materials and Methods except that the final complex concentration was 5 mM, cells were suspended in transport medium (30 ml) to an optical density of 1.2, and 5-ml aliquots were removed at each time and the radioactivity counted. The rate of 55Fe (■) and 14C (○) uptake were monitored simultaneously in the same assay by two-channel analysis. The rate of gallium-14C-lysineCAM (▵) uptake was monitored by following the transport of carbon 14.