Identification of Small-Molecule Antagonists of the Pseudomonas aeruginosa Transcriptional Regulator PqsR: Biophysically Guided Hit Discovery and Optimization
Identification of Small-Molecule Antagonists of the Pseudomonas aeruginosa Transcriptional Regulator PqsR: Biophysically Guided Hit Discovery and Optimization
复制标题
DOI：
10.1021/cb300208g
复制
发表时间：
2012-09-01
影响因子：
4
通讯作者：
Hartmann, Rolf W.
中科院分区：
文献类型：
--
作者：
Klein, Tobias;Henn, Claudia;Hartmann, Rolf W.
革兰氏阴性病原体铜绿假单胞菌产生细胞间烷基喹诺酮信号分子，即喹诺酮假单胞菌信号。pqs群体感应通信系统是铜绿假单胞菌的特征，它调节了毒力因子的产生。因此，我们认为pqs系统是限制铜绿假单胞菌致病性的新靶点。在这里，我们提出了针对pqs系统的关键参与者PqsR的小分子。合理的设计策略，结合表面等离子体共振生物传感器分析，导致PqsR结合物的鉴定。对大肠杆菌的热力学结合特征和功能表征进行了优化，得到了强效的羟肟酸衍生的PqsR拮抗剂11 （IC50 = 12.5 μ M）。其对铜绿假单胞菌（P. aeruginosa）的IC50值为23.6 μ M，显著降低了毒力因子pyocyanin的产生。除此之外，定点诱变与热力学分析一起提供了对蛋白质-配体相互作用的能量特征的见解。因此，所鉴定的PqsR拮抗剂是针对这一重要病原体的进一步药物设计工作的有希望的支架。
The Gram-negative pathogen Pseudomonas aeruginosa produces an intercellular alkyl quinolone signaling molecule, the Pseudomonas quinolone signal. The pqs quorum sensing communication system that is characteristic for P. aeruginosa regulates the production of virulence factors. Therefore, we consider the pqs system a novel target to limit P. aeruginosa pathogenicity. Here, we present small molecules targeting a key player of the pqs system, PqsR. A rational design strategy in combination with surface plasmon resonance biosensor analysis led to the identification of PqsR binders. Determination of thermodynamic binding signatures and functional characterization in E. coli guided the hit optimization, resulting in the potent hydroxamic acid derived PqsR antagonist 11 (IC50 = 12.5 mu M). Remarkably it displayed a comparable potency in P. aeruginosa (IC50 = 23.6 mu M) and reduced the production of the virulence factor pyocyanin. Beyond this, site-directed mutagenesis together with thermodynamic analysis provided insights into the energetic characteristics of protein-ligand interactions. Thus the identified PqsR antagonists are promising scaffolds for further drug design efforts against this important pathogen.