FIG. 3.

Iron and Fur regulation of gene expression. Western blot analysis showing iron-regulated protein expression. Wild-type MC58, the MC-Fko fur mutant, and the MC-Fko-C complemented mutant were grown under iron-replete (+) (supplemented GC medium) and iron-limiting (−) (supplemented GC medium with 25 μM desferal) conditions and were harvested at an OD₆₀₀ of 0.4 to 0.6. Equal amounts of total protein from each culture were fractionated by SDS-PAGE, blotted onto nitrocellulose filters, and stained with antiserum raised against the Fur protein (A), the Tbp2 protein (B), and constitutive protein NMB1870 as the negative control (C).