FIG. 5.

Effects of mntR and fur mutations on metalloregulation of the fur gene. Overnight cultures of strains carrying the fur-cat-lacZ reporter fusion were diluted 1:100 into minimal medium with either 1 μM Fe(III) (A) or 10 μM Fe(III) (B) and Mn(II) at 0, 0.1, 1, 10, 100, or 1,000 μM (left to right). Cells were grown to mid-log phase and collected for β-Gal assay. Note that the mntR mutant strain does not grow in concentrations of Mn(II) of 10 μM and greater (27), so no data were obtained for these conditions. WT, wild type.