呼吸系统复合体I的结构
Rouslan G Efremov1, Rozbeh Baradaran, Leonid A Sazanov
1Medical Research Council Mitochondrial Biology Unit, Wellcome Trust/MRC Building, Hills Road, Cambridge CB2 0XY, UK.
Nature
|May 28, 2010
概括
研究人员阐明了复杂I的结构,这是细胞能量生产中的关键酶. 这些发现揭示了新的质子转位机制,可能会影响神经退行性疾病研究.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 细胞呼吸 细胞呼吸
背景情况:
- 综合体I对于细胞能量生产和质子转移至关重要.
- 它的功能障碍与人类的神经退行性疾病有关.
- 之前的研究确定了其水友性域的结构.
研究的目的:
- 确定从大肠杆菌的复合体I的膜域的α-螺旋结构.
- 为了确定整个复杂的结构,我从Thermus thermophilus.
- 阐明复杂I中的质子转位的机制.
主要方法:
- 在3.9A和4.5A分辨率的X射线晶体学.
- 确定大肠杆菌复合体I的膜域结构.
- 确定整个Thermus thermophilus复合体I结构的确定.
主要成果:
- 大肠杆菌复合体I的膜域具有抗载体类子单元 (NuoL/M/N) 与14个保存的跨膜螺旋.
- 下单元 NuoL 包含一个独特的 110-A 长长的两 alpha-helix.
- 在Thermus thermophilus复合体I的L形结构中,发现了63个跨膜螺旋.
结论:
- 复杂的I架构表明,形状变化通过NuoL两螺旋的活塞式运动驱动质子转移.
- 这种运动可能会倾斜跨膜螺旋,促进质子运动.
- 了解这个机制,可以了解能源生产和疾病.
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