在线粒体呼吸复合体I中,横向的质子转移穿过类似反载体的子单元
Oleksii Zdorevskyi1, Amina Djurabekova1, Jonathan Lasham1
1Department of Physics, University of Helsinki Helsinki Finland vivek.sharma@helsinki.fi.
Chemical science
|June 16, 2023
概括
这项研究揭示了质子如何通过呼吸复合物I,这是ATP生成的关键酶. 新的发现突出显示了氨酸残留物和质子转移中的静电效应,修改了当前的模型.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 结构生物学 结构生物学
背景情况:
- 呼吸系统综合体I是线粒体ATP生成的关键质子,负责约40%的质子动力.
- 高分辨率冷电子显微镜 (cryo-EM) 数据已经确定了膜域中的水分子,但质子转移机制仍然不清楚.
研究的目的:
- 在呼吸复合体I的ND2子单元中建模明确的质子转移过程.
- 阐明膜结合的反载体类子单元内质子流动的路径和机制.
主要方法:
- 采用了多尺度计算机模拟.
- 使用高分辨率的结构数据来建模质子转移.
主要成果:
- 质子可以穿过抗载体类子单元的全部宽度,包括与膜平行的接口.
- 保存的氨酸残留物在催化水平质子转移方面发挥着重要作用.
- 远程静电效应通过降低能量屏障来促进质子转移.
结论:
- 已确定的质子转移途径和催化作用需要对呼吸系统复合体I质子的现有模型进行修订.
- 这项工作为细胞能量转导的基本机制提供了新的见解.
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