EefR突变通过激活AcrB-Null中神秘的多种药物排泄来驱动血脉性耐药性
Hao-Jie Shen1, Jun-Feng Wang1, Zheng-Jie Xue1
1College of Life Sciences, Zhejiang Chinese Medical University, Hangzhou, China.
Virulence
|September 29, 2025
概括
研究人员在大肠杆菌中发现了一种新的调节器EefR,该调节器控制了排泄系统. 这种系统增强了细菌对血红素和各种抗生素的耐药性,构成了全球健康的重大威胁.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
背景情况:
- 抗菌素耐药性 (AMR) 是一个主要的全球健康问题.
- 了解细菌适应机制对于开发有效的抗菌素抵抗策略至关重要.
- 来自Macleaya cordata的植物生物血红素 (SAN) 为细菌适应性研究提供了一个独特的压力因素.
研究的目的:
- 为了研究一个缺乏acrB的大肠杆菌菌株 (35218m) 适应血性 (SAN) 的适应机制.
- 确定导致大肠杆菌抗性SAN的遗传因素.
- 描述涉及多种药物排放的新型监管体系.
主要方法:
- 从一个缺乏acrB的大肠杆菌菌株中选择抗SAN的克隆.
- 基因分析以确定突变和调控元素.
- 对已识别的操作子的基因表达分析.
- 抗性配置文件的表型特征.
主要成果:
- 在SAN耐药克隆中发现了一种功能性不明的TetR调节器,EefR.
- EefR抑制了eefRABCD操作子,编码了一个RND-efflux (EefABC) 和一个MFS类型的出口器 (EefD).
- 过度表达的EefABC-EefD系统在acrB缺乏的大肠杆菌中产生了对SAN和其他抗生素的耐药性.
结论:
- EefR-EefABC-EefD系统代表了大肠杆菌中一种新的多药耐药性机制.
- 这种耐药性集群保留在肠杆菌群中,并存在于质粒上,这表明有可能广泛传播.
- 针对这种排放系统可能是对抗多药耐药细菌的策略.
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