染色体治疗推动了细菌转化和食原体之间的军备竞赛.
Min Jung Kwun1, Alexandru V Ion1, Katinka J Apagyi1
1MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, School of Public Health, Sir Michael Uren Hub, Imperial College London, 86 Wood Lane, London W12 0BZ, UK.
Molecular biology and evolution
|November 21, 2025
概括
细菌可以在转化过程中使用同源重组 (HR) 删除移动遗传元素 (MGE). 然而,一些MGE通过激活特定的生命周期来逃避删除,展示了与细菌能力机械的进化军备竞赛.
科学领域:
- 微生物学 微生物学
- 细菌遗传学 细菌遗传学
- 进化生物学 进化生物学
背景情况:
- 细菌转化允许通过同源重组 (HR) 吸收和整合外源DNA.
- 这一过程可以导致"染色体治愈",即删除整合性移动遗传元素 (MGE).
- 许多MGEs拥有逃避HR介导删除的机制,可能通过与ReCA-DNA丝相互作用.
研究的目的:
- 为了研究一种MGE类型的prophages如何在细菌转化过程中通过同源重组而逃避删除.
- 了解不同管调节系统 (C1型和ImmAR型) 在这种逃避过程中的作用.
- 探索菌体和细菌能力机械之间的进化相互作用.
主要方法:
- 研究了自然有能力的 *Streptococcus pneumoniae * * 中三种代表性传染体.
- 通过同源重组测定了通过同源重组测定的先删除率.
- 研究了对RECA-DNA丝和能力抑制剂DprA的prophage反应.
- 分析了影响prophage调节的突变对删除率和转化效率的影响.
主要成果:
- 所有三种测试的prophages都通过同源重组有效地被删除,类似于基替代率.
- 一个C1-调节的prophage,当突变时,显示了增加的删除,表明在转化过程中被ReCA-DNA丝片激活.
- 在对短暂刺激的反应中,ImmAR调节的prophages被切除为耐删除的伪解质原体.
- 一个prophage构成性地增加了DprA水平,抑制了能力诱导,从而转化.
结论:
- 在细菌转化过程中,食原体已经发展出各种策略,以逃避通过同源重组的删除.
- 进化军备竞赛存在于prophages和细菌能力机器之间,影响细菌多样化.
- 移动遗传元素可以阻碍同源重组,防止它们从细菌染色体中消除.
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