抑制细菌多种药物出口者的结构基础
Ryosuke Nakashima1, Keisuke Sakurai, Seiji Yamasaki
1Department of Cell Membrane Biology, Institute of Scientific and Industrial Research, Osaka University, Ibaraki, Osaka 567-0047, Japan.
Nature
|July 2, 2013
概括
皮里多皮里米丁衍生物通过与疏水陷结合来阻断多药物排放AcrB和MexB,从而阻碍它们的功能. 这一发现有助于开发新的抗生素来对抗格兰氏阴性病原体.
科学领域:
- 结构生物学 结构生物学
- 微生物学 微生物学
- 药物发现 药物发现 药物发现
背景情况:
- 像AcrB这样的多种药物排放载体是格拉姆阴性细菌多种药物耐药性的关键.
- 现有的排泄抑制剂缺乏临床效用,需要新的治疗策略.
- 墨西哥B和墨西哥Y是Pseudomonas aeruginosa的一个重要病原体的关键多药出口商.
研究的目的:
- 为了确定由pyridopyrimidine衍生物抑制AcrB和MexB的结构基础.
- 阐明pyridopyrimidines阻碍这些排泄的功能旋转的机制.
- 确定能够使特定抑制剂结合的结构特征,并指导新药的开发.
主要方法:
- 确定AcrB和MexB的结晶结构,并与一种pyridopyrimidine衍生物复合.
- 对抑制剂结合部位的分析,重点关注远端口袋和相关的疏水特征.
- 在AcrB,MexB和相关的载体MexY中结合相互作用的比较.
主要成果:
- 皮里多皮里米丁衍生物与AcrB和MexB的远端口袋中的特定的疏水陷结合.
- 这种结合在固体上阻碍了药物流出所必需的功能旋转.
- 在AcrB和MexB中的氨残留物 (Phe178) 通过π-π相互作用促进了密切的抑制剂结合,而MexY (Trp177) 中的氨阻止了这一点.
结论:
- 已识别的疏水陷是基于pyridopyrimidine的抑制剂的关键目标.
- 了解这些结构相互作用对于设计AcrB和MexB的强效和特定抑制剂至关重要.
- 这项工作为开发针对Pseudomonas aeruginosa中MexB和MexY的通用抑制剂奠定了基础.
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