Structural Analysis of the Regulatory Domain of ExsA, a Key Transcriptional Regulator of the Type Three Secretion System in Pseudomonas aeruginosa

Simple item page
dc.contributor.authorShrestha, Manishaen
dc.contributor.authorXiao, Yien
dc.contributor.authorRobinson, Howarden
dc.contributor.authorSchubot, Florian D.en
dc.contributor.departmentBiological Sciencesen
dc.date.accessioned2018-09-18T14:41:00Zen
dc.date.available2018-09-18T14:41:00Zen
dc.date.issued2015-08-28en
dc.description.abstractPseudomonas aeruginosa employs a type three secretion system to facilitate infections in mammalian hosts. The operons encoding genes of structural components of the secretion machinery and associated virulence factors are all under the control of the AraC-type transcriptional activator protein, ExsA. ExsA belongs to a unique subfamily of AraC-proteins that is regulated through protein-protein contacts rather than small molecule ligands. Prior to infection, ExsA is inhibited through a direct interaction with the anti-activator ExsD. To activate ExsA upon host cell contact this interaction is disrupted by the anti-antiactivator protein ExsC. Here we report the crystal structure of the regulatory domain of ExsA, which is known to mediate ExsA dimerization as well as ExsD binding. The crystal structure suggests two models for the ExsA dimer. Both models confirmed the previously shown involvement of helix α-3 in ExsA dimerization but one also suggest a role for helix α-2. These structural data are supported by the observation that a mutation in α-2 greatly diminished the ability of ExsA to activate transcription in vitro. Additional in vitro transcription studies revealed that a conserved pocket, used by AraC and the related ToxT protein for the binding of small molecule regulators, although present in ExsA is not involved in binding of ExsD.en
dc.description.versionPublished versionen
dc.format.mimetypeapplication/pdfen
dc.identifier.doihttps://doi.org/10.1371/journal.pone.0136533en
dc.identifier.eissn1932-6203en
dc.identifier.issue8en
dc.identifier.othere0136533en
dc.identifier.pmid26317977en
dc.identifier.urihttp://hdl.handle.net/10919/85036en
dc.identifier.volume10en
dc.language.isoenen
dc.publisherPLOSen
dc.rightsCreative Commons Attribution 4.0 Internationalen
dc.rights.urihttp://creativecommons.org/licenses/by/4.0/en
dc.titleStructural Analysis of the Regulatory Domain of ExsA, a Key Transcriptional Regulator of the Type Three Secretion System in Pseudomonas aeruginosaen
dc.title.serialPLOS ONEen
dc.typeArticle - Refereeden
dc.type.dcmitypeTexten

Files

Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
journal.pone.0136533.PDF
Size:
3.3 MB
Format:
Adobe Portable Document Format
Description:
Download

Collections

Scholarly Works, Biological Sciences