在社区嵌入进化过程中测试自然转变的适应性好处
Macaulay Winter1, Klaus Harms2, Pål Jarle Johnsen2
1European Centre for Environment and Human Health, University of Exeter Medical School, Environment and Sustainability Institute, Penryn Campus, TR10 9FE, UK.
Microbiology (Reading, England)
|August 1, 2023
概括
细菌中的自然转变,即环境DNA的吸收,在实验进化研究中没有显著影响进化适应性. 这表明了
科学领域:
- 微生物学和进化生物学
- 细菌遗传学和适应性的研究
背景情况:
- 自然转化使细菌能够获得外来DNA,潜在地增加遗传变异并帮助适应,类似于性繁殖.
- 自然转变的进化优势,特别是"性别假设",仍在争论中,从以前的实验进化研究中得到了混合的结果.
- 以前的研究往往忽视了物种相互作用的作用,理论上有利于转化等遗传交换机制的好处.
研究的目的:
- 在多物种社区背景下,研究细菌自然转化的适应性益处.
- 通过在波动选择下比较转化和非转化细菌菌株之间的适应性增长来测试自然转化的"性别假说".
主要方法:
- 在5周的时间里,自然可转化的野生型 *Acinetobacter baylyi* 和一个转化缺陷的 *∆comA* 突变体的实验进化.
- 在其他五种细菌物种的社区中培养细菌,以模拟强大和潜在波动的选择压力.
- 提供多种多样的*Acinetobacter*菌株作为DNA基质进行转化.
主要成果:
- 在转化和非转化*Acinetobacter baylyi*种群之间没有观察到体能增长的显著差异.
- 无论是转化菌株还是非转化菌株的种群,在各自的环境中都显示出不显著的健康改善.
- 野生型种群的演变频率略有增加,可能是由于遗传漂移而不是适应性选择.
结论:
- 在经过测试的实验条件下,自然转化能力并没有为*Acinetobacter baylyi*提供明显的健身优势.
- 在存在竞争物种的情况下,细菌的适应和身体状况的改善发生了,无论转化能力如何.
- 这项研究表明,除了自然转化之外的其他因素,可能是遗传漂移,可能会影响转化频率的演变.
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