在强制性细胞内细菌的实验进化过程中,基因组动力学和温度适应
Paul Herrera1, Lisa Schuster1, Markus Zojer1
1Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria.
Genome biology and evolution
|July 29, 2023
概括
这项研究表明,通过适应更高的温度,Protochlamydia amoebophila共生体进化减少了传染性. 这种权衡可能有助于从原生体转变为动物宿主,揭示了细菌基因组进化的洞察力.
科学领域:
- 微生物进化 微生物进化
- 细菌的适应 细菌的适应
- 交生研究 交生研究
背景情况:
- 使用自由生存微生物的进化实验是常见的,但对宿主相关细菌的研究是有限的.
- 严格与宿主相关的细菌广泛存在,对于理解微生物适应至关重要.
- 一种Acanthamoeba共生体的Protochlamydia amoebophila,可以作为与原生体相关的Chlamydiae的模型.
研究的目的:
- 为了研究有义务的细胞内共生体的进化和适应高温.
- 了解火力压力下的Protochlamydia amoebophila适应的分子基础.
- 探索从原生动物到内热动物宿主的进化飞跃.
主要方法:
- 在20°C和30°C的温度下建立了12个Protochlamydia amoebophila复制种群,510个细菌代.
- 利用感染性测试来评估进化的表型.
- 采用全基因组再测序,以识别遗传突变和适应性变化.
主要成果:
- 在30°C时进化的共生生物显示出传染性的总体减少.
- 许多非同义突变和小的indels被确定,与一些变体持久和达到高频率.
- 同一个温度调节中的突变基因表现出比调节之间的基因更高的相似性.
结论:
- 克拉米迪亚共生体的高温适应包括一个权衡,减弱传染性以减少宿主细胞负担.
- 这种适应策略为在宿主依赖下细胞内细菌的分子进化提供了洞察力.
- 这些发现表明,一种机制促进了进化过渡到内热动物宿主.
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