Inhibition of [59Fe]Ent and [14C]lactose uptake. E. coli MG1655 was grown in MOPS minimal medium until late exponential phase and independently assayed for its ability to accumulate [59Fe]Ent (A and C) and [14C]lactose (B and D) in the presence of either ebselen (A and B) or ST0082990 (C and D). We tested MG1655 in the absence of any inhibitors (circles), in the presence of CCCP at 25 μM (triangles), in the presence of ebselen at 25 (light gray squares), 200 (medium gray squares), and 250 (dark gray squares) μM, or in the presence of ST0082990 at 25 (light gray squares), 100 (medium gray squares), and 250 (dark gray squares) μM.