QsIA disrupts LasR dimerization in antiactivation of bacterial quorum sensing

Citation metadata

Publisher: National Academy of Sciences
Document Type: Author abstract; Report
Length: 168 words

Document controls

Main content

Abstract :

The human pathogen Pseudomonas aeruginosa coordinates the expression of virulence factors by using quorum sensing (QS), a signaling cascade triggered by the QS signal molecule and its receptor, a member of the LuxR family of QS transcriptional factors (LasR). The QS threshold and response in P. aeruginosa is defined by a QS LasR-specific antiactivator (QsIA), which binds to LasR and prevents it from binding to its target promoter. However, how QslA binds to LasR and regulates its DNA binding activity in QS remains elusive. Here we report the crystal structure of QslA in complex with the N-terminal ligand binding domain of LasR. QsIA exists as a functional dimer to interact with the LasR ligand binding domain. Further analysis shows that QsIA binding occupies the LasR dimerization interface and consequently disrupts LasR dimerization, thereby preventing LasR from binding to its target DNA and disturbing normal QS. Our findings provide a structural model for understanding the QsIA-mediated antiactivation mechanism in QS through protein-protein interaction. cell-cell communication | gene regulation www.pnas.org./cgi/doi/10.1073/pnas.1314415110

Source Citation

Source Citation   

Gale Document Number: GALE|A354858663