线粒体膜中的呼吸系统综合体I催化了超大规模的乌比基诺
Ryo Ikunishi1, Ryohei Otani1, Takahiro Masuya1
1Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kyoto, Japan.
The Journal of biological chemistry
|July 2, 2023
概括
NADH-ubiquinone氧化还原酶 (复合物I) 酶可以减少超大规模的ubiquinones (OS-UQs),挑战狭窄道模型. 这表明了酶.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 线粒体呼吸 线粒体呼吸
背景情况:
- NADH-ubiquinone (UQ) 氧化还原酶 (复合物I) 对于电子转移和质子转移至关重要.
- 一个狭窄的道模型提出了UQ如何访问活跃站点,但它的生理相关性是有争议的.
- 之前的研究给出了相矛盾的结果,关于通过复杂I来减少超大尺寸的UQ (OS-UQ).
研究的目的:
- 开发一种新的测定系统,以统一评估由本地复合物I.产生的OS-UQ减少.
- 研究本源酶中UQ反应部位对OS-UQs的可访问性.
- 重新评估UQ访问复杂I的规范道模型.
主要方法:
- 开发一种新型测定系统,使用与OS-UQ结合的子线粒体 (SMP) 和脂质体.
- 补充寄生性醇氧化酶用于回收减少了OS-UQ.
- 评估电子转移活动和质子转移与OS-UQ减少相结合.
主要成果:
- 所有测试的OS-UQ都在新的测试系统中被原生复合物I减少.
- 减少OS-UQ与质子转位相结合,表明功能活性.
- 结果与正规道模型相矛盾,表明可以灵活地进入UQ反应场所.
结论:
- 本地复合体I中的UQ反应腔是灵活开放的,允许OS-UQs访问.
- 洗剂溶解可能会改变分离酶中的空腔,阻碍OS-UQ访问.
- 根据这些发现,UQ访问的正规道模型需要修订.
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