氧化重新结合和逃逸的动力学在的过氧化酶中
Xiong Ye1, Anchi Yu, Paul M Champion
1Department of Physics and Center for Interdisciplinary Research on Complex System, Northeastern University, Boston, Massachusetts 02115, USA.
Journal of the American Chemical Society
|February 2, 2006
概括
这项研究报告了氧化 (NO) 重新结合到胡卜过氧化酶 (HRP) 的超快动力学. 与肌球蛋白不同,HRP表现出简单的指数NO重结,表明溶剂直接进入血红素口袋.
科学领域:
- 生物化学 生物化学
- 化学动力学 化学动力学
- 酶学 是一种酶学.
背景情况:
- 氧化 (NO) 在生物系统中起着至关重要的作用.
- 了解血红蛋白中NO连接体的动态是至关重要的.
- 马过氧化酶 (HRP) 是一个关键的酶与血红蛋白假体组.
研究的目的:
- 首次研究NO重结HRP的超快动力学.
- 为了比较HRP和肌球蛋白 (Mb) 之间的NO重结动力学.
- 为了确定酸 (BHA) 对NO联体逃逸率的影响,从HRP.
主要方法:
- 超快速的动力测量.
- 时间分辨率光谱学.
- 对双重组合和连接体逃脱动力学的分析.
主要成果:
- 无氧化重新结合HRP的双质动力学对于铁和铁形式都是指数的.
- 铁HRP显示NO双重组合时间常数为15-30 psi.
- 铁HRP的时间常数约为7ps.
- 从HRP中脱离NO联体的速率高度依赖于BHA的存在.
- 与Mb.不同的是,HRP证明了溶剂直接进入远端血口袋,与Mb.不同.
结论:
- 在HRP中简单的指数式NO重结表明,血红素放松不是Mb中观察到的非指数式重结的来源.
- BHA对NO逃逸率的显著影响表明它在调节连接体进入血口袋中的作用.
- 这些发现提供了对HRP和Mb之间关于NO结合的结构和动态差异的见解.
相关概念视频
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Cellular processes such as building and breaking down complex molecules occur through stepwise chemical reactions. Some of these chemical reactions are spontaneous and release energy, whereas others require energy to proceed. Cells often couple the energy-releasing reaction with the energy-requiring one to carry out important cell functions.
Energy in adenosine triphosphate or ATP molecules is easily accessible to do work. ATP powers the majority of energy-requiring cellular reactions. Cells...
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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...


