利芬素的选择性压力调节了菌根细菌基因组的突变速率和进化轨迹
E Cebrián-Sastre1, A Chiner-Oms2, R Torres-Pérez3
1Departamento de Biotecnología Microbiana, Centro Nacional de Biotecnología (CNB), CSIC, Madrid, Spain.
Microbiology spectrum
|July 12, 2023
概括
突变率的增加加快了菌根菌中耐利芬素耐药性的发展. 一种超可变菌株显示了增强的生存率和更快的适应这一关键的结核病抗生素.
科学领域:
- 微生物学 微生物学
- 遗传学 遗传学 是一个
- 进化生物学 进化生物学
背景情况:
- 利芬素是结核病治疗的关键一线抗生素.
- 利芬辛耐药性的增加构成了全球健康的重大挑战.
- 了解菌根细菌的适应机制对于对抗药物耐药性至关重要.
研究的目的:
- 为了研究 *Mycobacterium smegmatis* 对长期暴露于利芬素的基因组反应.
- 分析突变积累,并确定导致利芬素耐药性的适应性途径.
- 探索超变性在抗生素耐药性发展中的作用.
主要方法:
- 实验进化试验测定与不断增加的利芬素度.
- 突变积累试验与全基因组测序相结合.
- 野生型和 *ΔnucS* 突变菌株的比较分析.
主要成果:
- 抗生素治疗显著增加了野生类型细胞的全基因组突变率.
- 超可变的 *ΔnucS* 突变体表现出增强的生存率和加速的利芬辛耐药性.
- 确定了多种进化途径和适应基因,这些基因有助于抵抗.
- 突变率的增加与更高的耐药性和更好的生存率相关.
结论:
- 超变性可以是一个适应优势,促进抗生素耐药性的快速获得.
- 暴露于利芬素驱动了特定的基因组变化和向耐药性的多样化的进化轨迹.
- 这些发现为预防耐药性菌根杆菌感染提供了洞察力.
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