热爱体的适应性实验室进化趋向于降低生长温度的最佳状态
Maria Lehmann1, Christoph Prohaska1, Benjamin Zeldes1
1Department of Microbiology, Institute of Biological Sciences, University of Rostock, Rostock, Germany.
Frontiers in microbiology
|October 30, 2023
概括
研究人员通过实验在较低的温度下进化了一个热友细菌,T. kivui. 令人惊的是,而不是适应寒冷,热爱生物进化了较低的最佳生长温度,为早期生命进化提供了洞察力.
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:
- 在古代微生物中常见的热友性,通常被视为从中友性祖先的适应.
- 一个替代假设表明,最后一个普世共同祖先 (LUCA) 是热爱的,与 mesophily 是一个衍生的特征.
研究的目的:
- 为了实验性地研究从热爱者中进化的中性恋.
- 探索热友细菌在低于最佳温度下的适应性实验室进化 (ALE).
主要方法:
- 为实验进化选择了乙酸性细菌 *T. kivui* (最佳生长温度:66°C).
- 在低于最佳的温度下培养细菌,并在45°C进行连续转移,进行67次转移 (大约1. 180个世代). 在这个过程中,
- 分析了表型变化 (生长温度,细胞形态,脂质组成) 和基因组变化 (SNP).
主要成果:
- 适应菌株 (Adpt45_67) 在45°C时没有改善生长,但表现出转移到60°C的最佳生长温度.
- 形态变化包括更短,更厚的细胞,并观察到血原体的比例增加.
- 基因组分析揭示了67个单核酸多态 (SNP),包括转录调节者的突变.
结论:
- 这项研究提供了第一个实验证据,证明了从热爱者身上演化出一个较低的最佳生长温度.
- 这些发现有助于理解热友生物的寒冷适应和早期地球上生命的进化.
- 观察到的最佳生长温度变化背后的精确分子机制需要进一步阐明.
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