DNA-binding properties of MafR, a global regulator of Enterococcus faecalis.

Global transcriptional regulators play key roles during bacterial adaptation to environmental fluctuations. Protein MafR from Enterococcus faecalis was shown to activate the transcription of many genes on a genome-wide scale. We proposed that MafR is a global regulator of the Mga/AtxA family. Here, we purified an untagged form of the MafR protein and found that it binds to linear double-stranded DNAs in a nonsequence-specific manner. Moreover, multiple MafR units (likely dimers) bind sequentially to the DNA molecule generating multimeric complexes. On DNAs that contain the promoter of the mafR gene, MafR recognizes a potentially curved DNA region. We discuss that a characteristic of the Mga/AtxA regulators might be their ability to recognize particular DNA shapes across the bacterial genomes.