整个哺乳动物线粒体复合体的原子结构I
Karol Fiedorczuk1,2, James A Letts1, Gianluca Degliesposti3
1Institute of Science and Technology Austria, Klosterneuburg 3400, Austria.
Nature
|September 6, 2016
概括
我们确定了线粒体复合体I的原子结构, 这种结构揭示了其复杂的组合,并为其功能和与疾病有关的突变提供了洞察力.
科学领域:
- 生物化学
- 结构生物学
- 细胞呼吸
背景情况:
- 线粒体复合物I (NADH:ubiquinone oxidoreductase) 通过电子转移和质子转移对细胞能量产生至关重要.
- 它是呼吸链中最大的酶复合体,质量为970千多.
研究的目的:
- 确定羊类线粒体复合体I的几乎完整的原子结构.
- 阐明其功能,组装和与疾病的关系的结构基础.
主要方法:
- 在3.9 Å分辨率的冷电子显微镜.
- 交叉链接和质谱测绘实验.
- 保存的核心和超值子单位,辅助因子和脂质的分析.
主要成果:
- L 形线粒体复合体 I 的详细原子结构,包括 14 个核心和 31 个超值子单元.
- 电子传输组件 (FMN,铁硫集群) 和质子转移机器 (跨膜螺旋) 的识别.
- 观察两种可能与酶活性和调节相关的不同形状,与结合的脂质和辅助因子 (NADPH,胺) 影响相互作用.
结论:
- 这种结构为线粒体复合体I的机制,组合和成熟提供了前所未有的洞察力.
- 它能够详细分析与线粒体疾病相关的突变.
- 这些发现揭示了酶的形状驱动的合机制和活性-无活性过渡.
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