原核生物和其他微生物的序列离散物种:一个历史的视角和悬而未决的问题
Konstantinos T Konstantinidis1
1School of Civil and Environmental Engineering, and School of Biological Sciences Georgia Institute of Technology Atlanta Georgia USA.
mLife
|May 31, 2024
概括
微生物物种形成不同的集群,通常由85%-95%的基因组核酸标识分开. 生态差异化和重组率可能维持这些微生物物种边界.
科学领域:
- 微生物生态学 微生物生态学
- 基因组学就是基因组学.
- 进化生物学 进化生物学
- 微生物分类学 微生物分类学
背景情况:
- 定义微生物物种对于识别,调节和沟通至关重要.
- 基因组比较揭示了以序列离散的集群组织起来的 prokaryotic 多样性.
- 存在中间关系的生物也存在,可能代表不同的物种.
研究的目的:
- 研究微生物多样性组织成不同的集群.
- 探索维持这些集群的潜在机制,特别是重组和生态差异化.
- 促进对微生物物种概念的理解.
主要方法:
- 对数千个 prokaryotic 基因组和数百个元基因组的分析.
- 在不同种类中对基因组平均核酸标识 (ANI) 的比较.
- 对"中间"生物体的生态和功能特异性的证据的审查.
主要成果:
- 微生物多样性,包括原核生物,病毒和微生物真核生物,显示出序列离散集群的模式.
- 一种不连续的相关性,通常在85%-95%左右的基因组平均核酸标识,是始终观察到的.
- 生态差异化可以通过在95%核酸标识值周围限制同源重组来推动物种界限.
结论:
- 微生物物种可能存在于不同的集群中,由基因组和生态数据支持.
- 减少同源重组效率约95%核酸标识可能是维持物种界限的关键机制.
- 需要进一步的研究来严格测试将生态差异化和重组频率与物种定义联系在一起的假设.
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