FIG. 3.

Effects of iron availability on the expression of fur::luxAB (pHL01) in the wild type, the rpoS mutant, and the fur mutant. Iron in the medium was depleted by adding 0.2 mM 2,2′-dipyridyl to one of two cultures at the times indicated by the arrows. Culture OD₅₉₅ and luciferase activity were determined in the absence (closed symbols) and presence (open symbols) of 2,2′-dipyridyl. Luciferase activities (right panels) are expressed as normalized values. The results are from a single representative experiment from experiments performed in triplicate.