Molecular basis for the transcriptional regulation of an epoxide-based virulence circuit in Pseudomonas aeruginosa
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View abstract on PubMed
Summary
This summary is machine-generated.Pseudomonas aeruginosa uses a virulence factor, Cif, to worsen cystic fibrosis outcomes. Researchers discovered how the CifR regulator senses epoxides to control Cif expression, revealing new therapeutic targets.
Area Of Science
- Microbiology
- Structural Biology
- Molecular Biology
Background
- * Pseudomonas aeruginosa is an opportunistic pathogen causing severe cystic fibrosis (CF) lung infections.
- * The Cif virulence factor, an epoxide hydrolase, exacerbates CF disease by reducing CFTR and impairing resolution.
- * Cif expression is controlled by the TetR family repressor, CifR, the first identified epoxide-sensing bacterial regulator.
Purpose Of The Study
- * To elucidate the molecular mechanisms governing the Pseudomonas aeruginosa Cif virulence operon.
- * To investigate the interaction between CifR and its operator DNA.
- * To understand the activation mechanism of CifR in response to epoxide signaling.
Main Methods
- * Biochemical assays to study protein-DNA interactions and epoxide sensing.
- * X-ray crystallography to determine the structures of CifR alone and bound to operator DNA.
- * Structure-based analysis to identify key residues and conformational changes.
Main Results
- * Determined the first molecular structures of CifR alone and in complex with operator DNA.
- * Revealed significant conformational changes in CifR upon DNA binding, explaining gene regulation.
- * Identified the N-terminal extension of CifR as crucial for operator DNA recognition.
- * Demonstrated that Cys107 is essential for epoxide sensing and subsequent DNA release.
Conclusions
- * Uncovered the molecular basis for epoxide-mediated regulation of the Cif virulence factor in Pseudomonas aeruginosa.
- * Provided structural insights into CifR's DNA binding and conformational switching mechanism.
- * Highlighted Cys107 as a key residue for sensing and signaling pathway activation.
- * Established a foundation for developing novel therapeutic strategies targeting this critical virulence circuit.
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