聚米辛B的致命性需要能量依赖的外膜破坏
Carolina Borrelli1,2,3,4, Edward J A Douglas1,2, Sophia M A Riley1,2
1Centre for Bacterial Resistance Biology, Imperial College London, London, UK.
Nature microbiology
|September 29, 2025
概括
代谢活动对于抗生素polymyxin B (PmB) 对大肠杆菌等细菌的有效性至关重要. 静止阶段的细菌除非在代谢上活跃,否则会变得耐受,这揭示了抗生素耐受性的关键因素.
科学领域:
- 微生物学 微生物学
- 抗生素耐药性 抗生素耐药性
- 细菌生理学 细菌生理学
背景情况:
- 聚胺抗生素,包括聚胺B (PmB),向细菌膜中的脂多糖体 (LPS).
- 通过聚米克辛杀死细菌的精确机制仍然不完全理解.
研究的目的:
- 为了研究代谢活动在多素B致死性中的作用.
- 阐明聚米辛B在大肠杆菌中的作用方式.
主要方法:
- 利用原子力显微镜观察细菌表面的变化.
- 评估了外膜的LPS损失.
- 研究了代谢状态 (指数式与静止阶段) 和营养物质可用性对抗生素疗效的影响.
- 检查了MCR-1电阻决定因素的影响.
主要成果:
- 对大肠杆菌的Polymyxin B致命性取决于细菌的代谢活性.
- 静态阶段的细菌表现出对PmB的耐受性,除非提供碳源.
- 抗生素治疗诱导了外膜破坏和LPS损失,需要LPS合成和运输.
- 该MCR-1阻力决定因素阻断了PmB介导的LPS损失.
- 外膜的破坏促进了PmB进入内膜,通过能量独立透导致细胞死亡.
结论:
- 代谢活动对于polymyxin B的致命作用至关重要.
- 代谢不活性会使人对多素抗生素产生耐受性.
- 了解这种机制可以为针对抗聚素耐药细菌的策略提供信息.
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