FIG. 3.

Comparison of DtxR and IdeR binding sites. The sequences shown, except for the Streptomyces pilosus desA sequence, were identified by their ability to bind IdeR or DtxR, as measured by gel mobility and/or DNase footprinting assays. desA is repressed by iron (13), and since Streptomyces species have a DtxR homolog (14), it is assumed that the sequence shown here is an operator site for this protein. Other relevant references are cited in the text.