细菌的生活方式塑造了泛基体
Anna E Dewar1, Chunhui Hao1, Laurence J Belcher1
1Department of Biology, University of Oxford, Oxford OX1 3SZ, United Kingdom.
概括
细菌基因组的流动性因生活方式而异. 与宿主相关的细菌相比,与自由生活的物种相比,宿主相关的细菌表现出较少的流动性,这挑战了有效种群大小在这种变异中的作用.
科学领域:
- 微生物学 微生物学
- 基因组学就是基因组学.
- 进化生物学 进化生物学
背景情况:
- 细菌的泛基因组,即物种中完整的基因组,在物种之间在流动性 (基因多样性) 上有所不同.
- 两种假设,细菌的生活方式和有效人口规模,已被提出来解释这种变化.
- 之前的研究很难区分这些因素,因为它们的相关性和遗传学保存.
研究的目的:
- 研究细菌生活方式和有效种群大小在确定泛菌体流动性的因果关系.
- 通过先进的遗传学分析来分辨这些因素的相对重要性.
主要方法:
- 在126种细菌物种中进行了基于系系学的分析.
- 使用比较基因组学方法来评估泛基因组流动性.
- 使用统计方法来控制家族遗传关系.
主要成果:
- 与自由生活的相比,与宿主相关的细菌物种中的泛菌体流动性明显较低.
- 强制与宿主相关的,细胞内,致病性和较少运动的物种显示了最低的泛基因组流动性.
- 没有发现证据支持有效种群规模作为泛基因组流动性的直接驱动因素.
结论:
- 细菌的生活方式,特别是宿主协会及其相关特征,是泛基因组流动性的主要决定因素.
- 实际种群大小与瘤变异的相关性很可能是细菌生活方式间接影响的间接影响,而不是直接的因果关系.
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