在酸性压力下Salmonella enterica的适应性实验室进化
Mrinalini Ghoshal1,2, Tyler D Bechtel2, John G Gibbons2
1Department of Microbiology, University of Massachusetts, Amherst, MA, United States.
Frontiers in microbiology
|November 30, 2023
概括
适应性实验室进化 (ALE) 揭示了沙门氏菌对乙酸压力的适应性. 进化的菌株对抗生素的耐药性和交叉耐药性增加,病毒性和应激反应基因的遗传变化.
科学领域:
- 微生物学 微生物学
- 进化生物学 进化生物学
- 遗传学 是一个遗传学.
背景情况:
- 适应性实验室进化 (ALE) 是理解细菌适应性的关键.
- 沙门氏菌 (Salmonella Enteritidis) 是一个重要的细菌病原体.
研究的目的:
- 通过使用ALE.来研究沙门氏菌对酸的适应和演变.
- 了解S. Enteritidis.中的乙酸耐药性的遗传基础.
主要方法:
- 在使用亚最小抑制度 (亚MIC) 的乙酸时,使用了ALE.
- 在70天内,S. Enteritidis的四个进化系 (EL1-EL4) 得到了发展.
- 细菌全基因组测序是在进化的血统上进行的.
主要成果:
- 进化的血统 (EL2-EL4) 显示了对酸的最小抑制度 (MIC) 的增加,EL4 达到 35 mM.
- 进化血统的增长率增加,特别是EL4 (0.33h-1).
- 在进化血统中观察到抗生素 (西普洛克萨,美罗) 的MIC增加,EL4显示出更高的增加.
- 整个基因组测序揭示了毒性和应激反应基因 (phoP,phoQ, fhuA) 和基因组删除中的单核酸多态性.
结论:
- S. Enteritidis可以通过ALE适应酸压力,从而发展出增强的耐药性.
- 在S. Enteritidis中,酸的适应可以导致对抗生素的交叉耐药性.
- 毒性和应激反应基因的遗传修饰有助于酸性适应和潜在的致病性.
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