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来自阿斯加迪亚古生物的双组件系统传感器酶可能是真核细胞进化过程的证人
Felipe Padilla-Vaca1, Javier de la Mora2, Rodolfo García-Contreras3
1Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Noria Alta s/n, Guanajuato 36050, Mexico.
Molecules (Basel, Switzerland)
|July 14, 2023
概括
阿斯加达古拥有独特的两组分系统 (TCS),可以弥合细菌和真核生物的特征. 这些发现揭示了早期生命的进化和转变为真核生物的关键见解.
科学领域:
- 微生物学 微生物学
- 进化生物学 进化生物学
- 生物化学 生物化学
背景情况:
- 两组件系统 (TCS) 对细菌信号传导至关重要.
- 阿斯加达古生物群 (Asgardarchaeota) 是一种与真核生物起源有潜在联系的古生物群.
- 研究优先考虑了Asgardarchaeota中类似于真核生物的特征,而忽视了原核生物系统.
研究的目的:
- 为了分析Asgardarchaeota中的TCS传感器激酶的序列和结构特征.
- 为了研究阿斯加迪亚TCS和细菌同类之间的进化关系.
- 探索这些发现对真核细胞起源的含义.
主要方法:
- 从元基因组和基因组阿斯加迪安装组件中对TCS传感器激酶的生物信息分析.
- 同源性搜索用于识别细菌同源性和保存域.
- 预测蛋白质结构和定位,包括PAS域.
主要成果:
- 阿斯加德的TCS传感器激酶与细菌对应物呈现同质性,而洛基阿克则显示出更紧密的细菌联系.
- 在Lokiarchaeum和Candidatus Heimdallarchaeum中有一组不同的激酶将它们与典型的细菌TCS分开.
- AtoS和ArcB的同类物,以及其他传感器激酶域,表明与细菌代谢和共生有关.
结论:
- 阿斯加达古中的TCS激酶提供了从细菌向真核生物生命过渡的证据.
- 鉴定到的激酶突出显示了潜在的代谢联系,促进了共生关系.
- 阿斯加迪亚的TCS代表了 prokaryotes 和 eukaryotes 之间的关键进化桥梁.
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