氧气对 prokaryotic 进化 - 酶抑制的激进影响首先,不受抑制的基本生物合成第二,有氧呼吸第三
Natalia Mrnjavac1, Falk S P Nagies1, Jessica L E Wimmer1
1Institute of Molecular Evolution, Faculty of Mathematics and Natural Sciences, Heinrich Heine University Düsseldorf, Germany.
FEBS letters
|May 15, 2024
概括
分子氧 (O2) 刺激了 prokaryotes 中的新酶功能,使新的氧化和 O2 耐受性通路成为可能. 这对于在有氧环境中合成必需的辅助因子至关重要.
科学领域:
- 生物化学 生物化学
- 进化生物学 进化生物学
- 微生物学 微生物学
背景情况:
- 分子氧 (O2) 是一个稳定的二基,而依赖O2的酶利用了基机制.
- 氧气2的积累始于24亿年前,对地球的生物学产生了重大影响.
- 传统上,O2在进化过程中的作用与呼吸和能量产生有关.
研究的目的:
- 研究原核生物中由O2依赖酶驱动的主要生理适应.
- 了解O2依赖酶在辅因子生物合成和代谢进化中的作用.
- 重新评估氧气在节能之外的进化影响.
主要方法:
- 在 prokaryotes 中映射365个依赖氧的酶反应.
- 将这些反应与792个蛋白质家族的族系相关联.
- 分析这些酶的功能作用和进化起源.
主要成果:
- 依赖O2的酶主要促进了新的有机基质氧化和O2耐受性的替代代代谢途径.
- 这些酶主要不是为了节能,而是为了适应有氧环境.
- 依赖于O2的酶在祖先的无氧途径中进化为必要的辅因子生物合成 (例如,NAD +,血红素,叶绿素).
结论:
- 氧依赖酶的进化使得 prokaryotes 在氧气的存在下合成了重要的辅因子.
- 这种适应是随后有氧呼吸发展的关键先决条件.
- 氧气的进化影响超越了能量代谢,从根本上改变了生物化学能力.
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