Suneby Emma G, Herndon Leslie R, Schneider Tanya L
Department of Chemistry, Connecticut College , New London, Connecticut 06320, United States.
Department of Chemistry, Smith College , Northampton, Massachusetts 01063, United States.
ACS Infect Dis. 2017 Mar 10;3(3):183-189. doi: 10.1021/acsinfecdis.6b00163. Epub 2017 Jan 11.
Inhibition of quorum sensing in Pseudomonas aeruginosa is of interest as a possible antivirulence strategy for this pathogenic bacterium. The LasR regulator protein is important in coordinating gene expression in response to quorum sensing signaling molecules. One predominant strategy for LasR inhibition is the development of small-molecule antagonists that mimic the native autoinducer, though the mechanism by which they inactivate LasR is not known. This work reveals that multiple antagonists function by binding to and stabilizing LasR in a conformation that renders it unable to bind DNA. Further analysis of purified LasR complexed with known antagonists indicates that DNA binding can be recovered with the addition of native autoinducer, providing insights into the reversibility of ligand binding for this transcription factor. This in vitro assay could be used to assess future promising antagonists and complements existing cell-based reporter assays.
抑制铜绿假单胞菌群体感应作为该病原菌一种可能的抗毒力策略备受关注。LasR调节蛋白在响应群体感应信号分子协调基因表达方面很重要。抑制LasR的一种主要策略是开发模拟天然自诱导物的小分子拮抗剂，不过它们使LasR失活的机制尚不清楚。这项研究表明，多种拮抗剂通过与LasR结合并使其稳定在一种无法结合DNA的构象中发挥作用。对与已知拮抗剂复合的纯化LasR的进一步分析表明，添加天然自诱导物后可恢复DNA结合，这为该转录因子配体结合的可逆性提供了见解。这种体外检测方法可用于评估未来有前景的拮抗剂，并补充现有的基于细胞的报告基因检测。
