两种类型的DNA回旋酶抑制剂引起了不同的进化轨迹,导致了格兰负病原体的耐药性
Semen A Leyn1, James E Kent1, Jaime E Zlamal1
1Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, USA.
npj antimicrobials and resistance
|January 22, 2025
概括
了解抗菌素耐药性机制是开发新药的关键. 这项研究表明,大肠杆菌和A. baumannii对GP6的耐药性主要涉及排泄的上调调节,与西普洛素耐药性不同.
科学领域:
- 微生物学 微生物学
- 遗传学 遗传学 是一个
- 药理学 药理学是指药理学的学科.
背景情况:
- 抗菌素耐药性 (AMR) 构成了全球健康的重大威胁.
- 开发新的抗微生物药物需要对抗药性机制有深入的了解.
- 研究耐药性进化有助于设计具有抗性降低的药物.
研究的目的:
- 调查埃舍里奇亚大肠杆菌和Acinetobacter baumannii中对DNA旋酶/拓酶TriBE抑制剂GP6的耐药性获得的进化动态.
- 为了比较GP6的抗药性机制与西普洛素 (CIP) 的抗药性机制.
主要方法:
- 在连续培养装置 (病态定位器) 中利用实验进化.
- 采用了进化文化的全基因组测序.
- 鉴定耐药分离物的特征,以确定耐药机制.
主要成果:
- 通过目标突变 (GyrB子单元) 和排水上调 (AcrAB/TolC,AdeIJK,MdtK) 进化了GP6耐药性.
- 溢出上调是GP6阻力的主要机制,有时会先于或取代目标修改.
- 抗GP6的分离体对西普洛素呈现交叉耐药性,但不是反之亦然.
结论:
- 对GP6和西普洛素的耐药性涉及不同的进化轨迹和向突变谱.
- 流量的上调在GP6耐药性中起着至关重要的作用,使其对西普洛素产生交叉耐药性.
- 这项研究提供了对设计具有最小抗药性潜力的新型抗菌剂的见解.
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