通过细胞氧化酶进行质子的机械原理
Kristina Faxén1, Gwen Gilderson, Pia Adelroth
1Department of Biochemistry and Biophysics, The Arrhenius Laboratories for Natural Sciences, Stockholm University, SE-106 91 Stockholm, Sweden.
Nature
|September 9, 2005
概括
在细胞染色体c氧化酶 (CytcO) 中进行质子的分子机制得到了阐明. 质子与在催化部位将质子转移到氧气相结合,而不是内部电子转移.
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:
- 有氧生物的细胞呼吸利用膜结合的蛋白质复合体进行电子转移到氧气中.
- 这一过程产生了ATP合成所必需的跨膜电化学质子梯度.
- 细胞染色体c氧化酶 (CytcO) 是终端酶复合体,将O2降低为H2O,并将质子穿过膜.
研究的目的:
- 确定在CytcO中由电子转移驱动的质子的分子机制.
- 为了阐明CytcO在氧气减少过程中如何在膜上转移质子.
主要方法:
- 这项研究研究了CytcO.O.中电子转移和质子转位之间的机械合.
- 重点放在催化部位上,在那里氧气被减少为水.
主要成果:
- 在CytcO中的质子是机械合的,在催化部位将质子转移到O2.
- 这种合发生,而不是与复合体内的内部电子转移事件联系在一起.
结论:
- 这些发现表明了氧化还原驱动质子运行的新原理.
- 这种机制对通过CytcO进行质子转位的可能分子途径施加了显著的约束.
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