Pseudomonas aeruginosa SutA wedges RNAP lobe domain open to facilitate promoter DNA unwinding.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 35859063.
- Also identified by DOI 10.1038/s41467-022-31871-7 and PMC identifier 9300723.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Pseudomonas aeruginosa (Pae) SutA adapts bacteria to hypoxia and nutrition-limited environment during chronic infection by increasing transcription activity of an RNA polymerase (RNAP) holoenzyme comprising the stress-responsive σ factor σ<sup>S</sup> (RNAP-σ<sup>S</sup>). SutA shows no homology to previously characterized RNAP-binding proteins. The structure and mode of action of SutA remain unclear. Here we determined cryo-EM structures of Pae RNAP-σ<sup>S</sup> holoenzyme, Pae RNAP-σ<sup>S</sup> holoenzyme complexed with SutA, and Pae RNAP-σ<sup>S</sup> transcription initiation complex comprising SutA. The structures show SutA pinches RNAP-β protrusion and facilitates promoter unwinding by wedging RNAP-β lobe open. Our results demonstrate that SutA clears an energetic barrier to facilitate promoter unwinding of RNAP-σ<sup>S</sup> holoenzyme.
Medical subject headings
- DNA-Directed RNA Polymerases
- Pseudomonas aeruginosa