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

ABSTRACT: 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.

SUBMITTER: Ruiz-Cruz S

PROVIDER: S-EPMC5947639 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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

Ruiz-Cruz Sofía S Moreno-Blanco Ana A Espinosa Manuel M Bravo Alicia A

FEBS letters 20180326 8

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 sequentiall ...[more]

PMID: 29537484

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