Structure of the Escherichia coli antitoxin MqsA (YgiT/b3021) bound to its gene promoter reveals extensive domain rearrangements and the specificity of transcriptional regulation.

ABSTRACT: Bacterial cultures, especially biofilms, produce a small number of persister cells, a genetically identical subpopulation of wild type cells that are metabolically dormant, exhibit multidrug tolerance, and are highly enriched in bacterial toxins. The gene most highly up-regulated in Escherichia coli persisters is mqsR, a ribonuclease toxin that, along with mqsA, forms a novel toxin·antitoxin (TA) system. Like all known TA systems, both the MqsR·MqsA complex and MqsA alone regulate their own transcription. Despite the importance of TA systems in persistence and biofilms, very little is known about how TA modules, and antitoxins in particular, bind and recognize DNA at a molecular level. Here, we report the crystal structure of MqsA bound to a 26-bp fragment from the mqsRA promoter. We show

SUBMITTER: Brown BL 

PROVIDER: S-EPMC3023523 | biostudies-literature | 2011 Jan

REPOSITORIES: biostudies-literature