在仿生复合体中,细胞染色体c的合蛋白和电子转移动态的分子基础
Damián Alvarez-Paggi1, Diego F Martín, Pablo M DeBiase
1Departamento de Química Inorgánica, Analítica y Química Física/INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pab. 2, piso 1, C1428EHA-Buenos Aires, Argentina.
Journal of the American Chemical Society
|April 6, 2010
概括
固定细胞染色体c (Cyt) 中的电子转移 (ET) 受蛋白质动力学和方向的影响. 首选的绑定配置没有优化电子合,揭示了控制ET速率的复杂相互作用.
科学领域:
- 生物物理化学 生物物理化学
- 电化学 电化学 电化学
- 计算生物学 计算生物学
背景情况:
- 在电极上的氧化还原蛋白中,直接的电子转移 (ET) 对生物电子设备至关重要.
- 在蛋白质ET率中观察到的异常距离依赖性缺乏明确的分子解释.
- 黄金表面上的细胞染色体c (Cyt) 固定是研究蛋白质电化学的模型系统.
研究的目的:
- 研究控制静电固定细胞染色体c的电子转移速率的因素.
- 阐明蛋白质定向,动力学和电子合之间的关系.
- 为了解蛋白质电化学中的实验观测提供了分子基础.
主要方法:
- 分子动力学 (MD) 模拟以建模蛋白质-电极相互作用.
- 结合能量的计算,以确定首选的蛋白质配置.
- 电子通路和电子合矩阵的分析.
主要成果:
- 通过氨酸残留物识别了Cyt的首选结合方向,从而产生不同的双极时刻.
- 证明了热力学偏好的方向与最佳电子合不一致.
- 揭示了蛋白质动力学 (重定向和热波动) 微调电子合.
结论:
- 固定Cyt中的电子转移是由蛋白质动力学和道化概率之间的相互作用决定的.
- 蛋白质的方向和动态显著影响ET速率,特别是在应用电场下.
- 该研究为实验 (光谱) 电化学数据和对生理ET机制的洞察提供了分子解释.
相关概念视频
Electron Transport Chain: Complex III and IV
During the electron transport chain, electrons from NADH and FADH2 are first transferred to complexes I and II, respectively. These two complexes then transfer the electrons to ubiquinol, which carries them further to complex III. Complex III passes the electrons across the intermembrane space to Cyt c, which carries them further to complex IV. Complex IV donates electrons to oxygen and reduces it to water. As electrons pass through complexes I, III, and IV, the energy released aids the pumping...
The Supercomplexes in the Crista Membrane
The mitochondrial cristae membrane is the primary site for the oxidative phosphorylation (OXPHOS) process of energy conversion mediated through respiratory complexes I to V. These complexes have been widely studied for decades, and it has been proven that they form supramolecular structures called respiratory supercomplexes (SC). These higher-order complexes may be crucial in maintaining the biochemical structure and improving the physiological activity of the individual complexes while...
Electron Transport Chains
The final stage of cellular respiration is oxidative phosphorylation that consists of two steps: the electron transport chain and chemiosmosis. The electron transport chain is a set of proteins found in the inner mitochondrial membrane in eukaryotic cells. Its primary function is to establish a proton gradient that can be used during chemiosmosis to produce ATP and generate electron carriers, such as NAD+ and FAD, that are used in glycolysis and the citric acid cycle.
The ETC is comprised of...
The ETC is comprised of...
Electron Transport Chain: Complex I and II
The mitochondrial electron transport chain (ETC) is the main energy generation system in the eukaryotic cells. However, mitochondria also produce cytotoxic reactive oxygen species (ROS) due to the large electron flow during oxidative phosphorylation. While Complex I is one of the primary sources of superoxide radicals, ROS production by Complex II is uncommon and may only be observed in cancer cells with mutated complexes.
ROS generation is regulated and maintained at moderate levels necessary...
ROS generation is regulated and maintained at moderate levels necessary...
Electron Transport Chain Components
The electron transport chain (ETC) is a crucial metabolic pathway that facilitates energy conversion in prokaryotic and eukaryotic cells. In eukaryotes, the ETC comprises four membrane-associated protein complexes in the inner mitochondrial membrane. In prokaryotes, the ETC in the plasma membrane can vary in composition, with fewer or different complexes depending on the organism and environmental conditions. These complexes transfer electrons from electron donors, such as NADH and FADH2, to...
Protein Dynamics in Living Cells
Different fluorescence-based techniques are used to study the protein dynamics in living cells. These techniques include FRAP, FRET, and PET.
Fluorescent recovery after photobleaching (FRAP) is a fluorescent-protein-based detection technique used to quantify protein movement rates within the cell. This method exposes a small portion of the cell to an intense laser beam. The laser beam causes permanent photobleaching of the fluorophore-tagged proteins in the exposed region. As the bleached...
Fluorescent recovery after photobleaching (FRAP) is a fluorescent-protein-based detection technique used to quantify protein movement rates within the cell. This method exposes a small portion of the cell to an intense laser beam. The laser beam causes permanent photobleaching of the fluorophore-tagged proteins in the exposed region. As the bleached...


