一步一步的O O
Yudhajeet Basak1, Jae-Hun Jeoung1, Lilith Domnik1
1Institut für Biologie, Humboldt-Universität zu Berlin, Unter den Linden 6, 10099, Berlin, Germany.
Angewandte Chemie (International ed. in English)
|June 6, 2023
概括
暴露在空气中通过多步骤的过程使一氧化碳脱酶 (CODHs) 不活化. 最初的可逆步骤涉及离子的连接物阻断,随后是不可逆转的损失和结构重组.
科学领域:
- 生物化学和酶学 生物化学和酶学
- 生物有机化学 生物有机化学
- 微生物的新陈代谢
背景情况:
- 含有Ni,Fe的一氧化碳脱酶 (CODHs) 是无氧微生物中的关键酶,催化二氧化碳转化为一氧化碳的可逆转化.
- CODH对氧气非常敏感,在暴露在空气中时迅速失去活性,这种现象的潜在机制仍然不太清楚.
研究的目的:
- 为了阐明CODH-II在暴露在空气中的金属中心发生的依赖时间的结构变化.
- 为了确定特定的步骤和分子事件,负责CODHs在氧气存在时的失活.
主要方法:
- 分析CODH-II金属中心因空气暴露而产生的依赖时间的结构变化.
- 对化物联结对离子对氧诱导分解的保护作用的研究.
主要成果:
- 通过空气使CODH无活化是一个多步骤的过程,由一个可逆步骤开始,其中一个Ni,Fe桥接联体 (μ-硫化物或化物) 阻断了Ni离子的开放协调部位.
- 在离子中由化物稳定集群,证实了该地点的氧气攻击.
- 不可逆转的阶段涉及的损失,铁离子的重新排列和硫化连接物的消失.
结论:
- 这些发现表明,可逆的还原反应激活机制可以保护CODHs免受短暂的过氧化.
- 了解这些失活路径对于利用生物技术应用中CODH活性至关重要.
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