PerR is a positive regulator of staphyloferrin B-mediated iron acquisition in Staphylococcus aureus

Due to the concerted action of host iron (Fe) sequestration mechanisms, the ability of bacterial pathogens to overcome this nutritional immunity is required for infection. S. aureus expresses an arsenal of Fe acquisition systems the expression of which are coordinated primarily through a well-characterized Fe-sensing transcriptional regulator, Fur.

Here, from a screen to identify S. aureus mutants defective for iron-restricted growth, we identified several where genome sequencing identified mutations in the perR gene, encoding a transcriptional regulator involved in resistance to oxidative stress. RNA-seq identified that perR mutants express significantly less transcript from the staphyloferrin B biosynthetic operon, sbn, during growth under Fe starvation. These results were consistent with our finding that perR mutants grew poorly in iron-deficient media in a staphyloferrin B-dependent manner.