质子合电子转移驱动了细胞c氧化酶的质子
Ilya Belevich1, Michael I Verkhovsky, Mårten Wikström
1Helsinki Bioenergetics Group, Institute of Biotechnology, University of Helsinki, FIN-00014 University of Helsinki, Helsinki, Finland.
Nature
|April 7, 2006
概括
细胞呼吸中的电子转移与细胞染色体c氧化酶的质子送相结合. 这项研究揭示了从血中a到氧降低部位的电子转移通过内部质子转移启动了质子机制.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 生物能源学 生物能源学
背景情况:
- 细胞呼吸配对电子转移到质子转移以进行能量转导.
- 电化学质子梯度为ATP合成等细胞反应提供动力.
- 细胞染色体c氧化酶对于氧气减少和呼吸链中的质子是至关重要的.
研究的目的:
- 为了阐明通过细胞染色体c氧化酶进行质子的机制.
- 为了研究内部电子转移和质子转移之间的合.
- 澄清海姆甲和O2降解点在启动质子的作用.
主要方法:
- 实时监控电荷转移的情况.
- 在细胞染色体c氧化酶中同时观察电子转移.
- 质子吸收和释放的动态分析.
主要成果:
- 电子从血中转移到O2减少部位被确定为质子的触发因素.
- 这种电子转移在动力学上与内部的矢量质子转移有关.
- 质子机制是在质子从水面吸收/释放之前启动的.
结论:
- 从血a到O2还原部位的内部电子转移直接驱动了细胞染色体c氧化酶质子.
- 质子是机械地与内部电子转移相结合,反驳了之前的动力学建议.
- 这一发现澄清了生物能量转导的关键步骤.
相关概念视频
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...
Chemiosmosis
Oxidative phosphorylation is a highly efficient process that generates large amounts of adenosine triphosphate (ATP), the basic unit of energy that drives many cellular processes. Oxidative phosphorylation involves two processes— the electron transport chain and chemiosmosis.
Electron Transport Chain
The electron transport chain involves a series of protein complexes on the inner mitochondrial membrane that undergo a series of redox reactions. At the end of this chain, the electrons reduce...
Electron Transport Chain
The electron transport chain involves a series of protein complexes on the inner mitochondrial membrane that undergo a series of redox reactions. At the end of this chain, the electrons reduce...
The Electron Transport Chain
The electron transport chain or oxidative phosphorylation is an exothermic process in which free energy released during electron transfer reactions is coupled to ATP synthesis. This process is a significant source of energy in aerobic cells, and therefore inhibitors of the electron transport chain can be detrimental to the cell's metabolic processes.
Inhibitors of the electron transport chain
Rotenone, a widely used pesticide, prevents electron transfer from Fe-S cluster to ubiquinone or Q in...
Inhibitors of the electron transport chain
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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...
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...
Chemiosmosis and ATP Synthesis
The electron transport chain is a critical component of cellular respiration, occurring in the inner mitochondrial membrane. It facilitates the transfer of high-energy electrons from reduced cofactors NADH and FADH₂ to molecular oxygen, the final electron acceptor. This transfer of electrons through a series of protein complexes is tightly coupled to the translocation of protons across the membrane, generating a proton gradient essential for ATP synthesis.Electron Flow and Proton...


