氧减少酶的起源是在大氧化事件之后发生的,并结束了洛马贡迪游览
Katharina Trost1, Robert B Gennis2, John F Allen3
1Department of Biology, Institute for Molecular Evolution, Heinrich Heine University of Duesseldorf, 40225, Duesseldorf, Germany.
Biochimica et biophysica acta. Bioenergetics
|December 3, 2025
概括
地球的氧气历史显示大气氧气水平在大氧化事件 (GOE) 发生之前是可以忽略不计的. 对氧减少酶的新研究表明,在GOE之后,氧积累的四个阶段模型,稳定在2%的大气氧气.
科学领域:
- 进化生物学是进化的生物学.
- 地质化学 地质化学
- 分子进化的分子进化.
背景情况:
- 大约24亿年前的大氧化事件 (GOE) 标志着大气氧气的显著增加,但GOE前的氧气水平仍在争论中.
- 了解氧化代谢的演变对于进化生物学和地球历史至关重要.
研究的目的:
- 调查氧减少酶的进化历史,并提出围绕GOE大气氧气积累的模型.
- 分析氧还原酶基因在 prokaryotic 进化时间线上的分布.
主要方法:
- 在分子时间尺度上分析氧减少酶 (cytochrome bd-oxidases,血铜氧化酶,替代氧化酶) 的基因分布.
- 将基因进化与大气氧气积累的拟议模型进行比较.
主要成果:
- 氧减少酶起源于GOE之后,大约24亿年前,并经历了广泛的横向基因转移.
- 提出了氧气积累的四个阶段模型,在最初的菌氧气产量上限为2%的大气氧气,这是由于酶抑制.
- 洛马贡迪13C异常与这些早期氧气条件下的二氧化碳埋葬和RuBisCO同位素歧视有关.
结论:
- 大气中的氧气在GE和Lomagundi游览期间保持在2%以下.
- 氧降解酶的演变和传播对呼吸过程至关重要,并导致在2%氧气下达到平衡.
- 这项研究为了解早期地球的氧气动态和 prokaryotic 进化提供了一个新的框架.
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