整个呼吸系统综合体的晶体结构
Rozbeh Baradaran1, John M Berrisford, Gurdeep S Minhas
1Medical Research Council Mitochondrial Biology Unit, Wellcome Trust/MRC Building, Hills Road, Cambridge CB2 0XY, UK.
Nature
|February 19, 2013
概括
完好无损的复合体I的第一个晶体结构揭示了它的细胞能量生产机制. 这是一种呼吸系统酶.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 分子生物学分子生物学
背景情况:
- 复合物I是呼吸链中的关键酶,对细胞能量生产至关重要.
- 综合体I的功能障碍与人类的神经退行性疾病有关.
研究的目的:
- 确定Thermus thermophilus的整个完好无损的复合体I的高分辨率晶体结构.
- 阐明复合体I中质子转移和能量合的结构基础.
主要方法:
- 在3.3 Å分辨率的X射线晶体学.
- 对536-kDa复合物的分析,包括16个子单元和9个铁硫.
主要成果:
- 揭示了由连接的半通道形成的新型第四个质子转位通路.
- 确定了一个与质子通道相关的异常封闭的子结合部位.
- 提出了一种涉及灵活中心轴传播形状变化的机制.
结论:
- 独特的离子结合室和质子通路促进了高效的能量转导.
- 该结构提供了对质子的机制及其与疾病相关性的见解.
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