一个生态进化模型,通过对原体的接地和积累来生存素
Pavithra Anantharaman Sudhakari1, Bhaskar Chandra Mohan Ramisetty2
1Laboratory of Molecular Biology and Evolution, School of Chemical and Biotechnology, SASTRA Deemed University, 312@ASK1, Thanjavur, India.
Microbial ecology
|October 16, 2023
概括
大多数细菌携带多个菌体,这是过去菌体感染的残余. 细菌可以通过"接地"这些菌体来获得超级感染免疫力,从而防止新的感染.
科学领域:
- 微生物学 微生物学
- 进化生物学 进化生物学
- 基因组学就是基因组学.
背景情况:
- 温带菌体作为菌体集成到细菌基因组中,大多数细菌含有多个菌体元素.
- 推动细菌基因组中的prophage积累的进化和生态因素仍然不太清楚.
- 前体可以赋予对超级感染的抵抗力,这种现象在当地废水溶解物体中观察到.
研究的目的:
- 调查细菌基因组,特别是大肠杆菌 (Escherichia coli) 中的prophages的流行和分布.
- 了解进化动态和生态因素,有助于扩散的积累.
- 探索菌体在对菌体超级感染的细菌防御中的作用.
主要方法:
- lysogenic 和 non-lysogenic 细菌分离物的基因组分析.
- 来自全球不同来源的2180多个大肠杆菌基因组的大规模比较基因组分析.
- 分析了523个细菌基因组,具体来自废水分离物.
- 生态进化建模以模拟体积累动态.
主要成果:
- 在分析的大肠杆菌基因组中确定了大量的prophages,平均每基因组约有5个prophages.
- 在lysogenic和non-lysogenic两种菌株中都发现了食原体,这表明它们通常是无法切割的"接地"遗迹.
- 前体分布表明随机发生和广泛的横向转移在细菌基因组.
- 生态进化模型支持这样一个假设:细菌通过接地菌体来赢得菌体冲突,从而赋予超级感染免疫力.
结论:
- 前体在细菌基因组中很常见,通常代表了过去感染的不可切除的残留物.
- 横向基因转移在细菌群体内和细菌群体之间传播细胞的分布中起着重要作用.
- 菌体的"接地"是细菌实现超级感染免疫的关键策略,影响细菌-菌体共同进化的动态.
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