使用I型反应中心的Chloroflexota无氧光
J M Tsuji1,2,3, N A Shaw4, S Nagashima5,6
1University of Waterloo, Waterloo, Ontario, Canada. jackson.tsuji@jamstec.go.jp.
Nature
|March 14, 2024
概括
研究人员在湖水中发现了一种新型无氧光营养细菌. 这种细菌使用I型反应中心 (RCI),但与II型反应中心 (RCII) 光合作用共享祖先,揭示了光合作用进化的新见解.
科学领域:
- 微生物学
- 进化生物学
- 生物化学
背景情况:
- 遗传学上的差距阻碍了对光进化的理解.
- 之前的研究发现了具有不同反应中心的不同组光营养细菌.
研究的目的:
- 通过探索光合作用细菌中的基因差距来研究光合作用的进化.
- 描述一种来自Chloroflexota族的新型光菌.
主要方法:
- 化北极盾湖水样.
- 培养无氧光营养细菌
- 生理学,基因组学和转录组学分析.
主要成果:
- 在Chloroflexota中培养了一种未知的无氧光营养细菌.
- 这种细菌利用I型反应中心 (RCI),但具有与II型反应中心 (RCII) 光相关的特征 (,细菌).
- 基因组数据表明,使用RCI和RCII的Chloroflexia具有共同的光性祖先.
结论:
- 在光合作用进化过程中,Chloroflexota属是一种过渡形式.
- 这一发现为了解细菌中的光多样化提供了新的背景.
- 在基因相关的细菌中存在相反的光模式,在Chloroflexota类中保存.
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