通过第二个电子减少细胞染色体c氧化酶会导致质子转位
Maarten Ruitenberg1, Aimo Kannt, Ernst Bamberg
1Department of Biophysical Chemistry, Max-Planck-Institut für Biophysik, Kennedyallee 70, D-60596 Frankfurt/Main, Germany.
Nature
|May 3, 2002
概括
细胞染色体c氧化酶的质子发生在还原阶段,而不仅仅是氧化阶段. 这项研究表明,质子发生在第二个电子转移时,澄清了细胞呼吸机制.
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:
- 细胞染色体c氧化酶对于细胞呼吸至关重要,减少氧气到水.
- 这种酶的质子对于ATP合成至关重要,但人们对其了解甚少.
- 以前的模型仅将质子与氧化阶段 (3/4电子转移) 联系在一起.
研究的目的:
- 为了研究细胞染色体c氧化酶中质子的时间和机制.
- 为了澄清质子是否发生在电子转移的还原阶段.
主要方法:
- 测量膜电潜的方法.
- 从酶的定义的一电子减少状态开始.
- 控制的电子转移实验.
主要成果:
- 第二个电子转移到细胞染色体c氧化酶中会诱导电荷转移.
- 这种电荷转移对应于一个质子的送.
- 质子发生独立于之前的氧化阶段.
结论:
- 细胞染色体c氧化酶的质子可以在还原阶段 (1st/2nd电子转移) 发生.
- 这一发现挑战了以前的模型,并提出了对质子转移的修订机制.
- 这项研究为细胞呼吸的生物能学提供了关键的见解.
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