一个基于蛋白质的模型,可以解释氧化和光合作用酸化中的能量合
1Department of Biochemistry, Cell and Systems Biology, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, L69 7ZB, UK; The Novo Nordisk Foundation Centre for Biosustainability, Technical University of Denmark, Building 220, Søltofts Plads, 2800 Kgs Lyngby, Denmark; Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch, Private Bag X1, Matieland, 7602, South Africa.
Biochimica et biophysica acta. Bioenergetics
|August 17, 2024
概括
化学体质的合方式
科学领域:
- 生物化学 生化学
- 生物能源学 生物能源学
- 细胞呼吸 细胞呼吸
背景情况:
- 化学合假说提出,质子运动力 (pmf) 是将电子运输和ATP合成联系起来的高能中间体.
- 包括人工质子梯度在内的实验证据支持了这一假设,表明pmf驱动酸化.
- 然而,观察到的pmf in vivo值和实验值引发了关于pmf对酸化的充分性的问题.
研究的目的:
- 批判性地评估化学合假设在解释酸化的实验观测中的充分性.
- 探索生物系统中能量合的替代模型.
- 调和大量的文献,这些文献似乎与当前的chemiosmotic模型不一致.
主要方法:
- 对酸化和质子运动力测量的现有文献进行分析.
- 对实验数据的审查,包括两阶段酸化,人工pmf驱动酸化和直接pmf测量.
- 考虑替代模型,例如基于假体的电荷分离.
主要成果:
- 对pmf驱动酸化的实验值表明,电子运输产生的pmf可能不足.
- 直接和间接的pmf测量,包括使用微电极和穿透膜探头的测量,表明pmf值非常低.
- 对先前公认的高pmf值和其他不一致性的陈旧解释挑战了化学体质模型.
结论:
- 目前所理解的化学合假设不足以解释观察到的能量合和酸化现象.
- 一个基于假体的电荷分离模型提供了一个潜在的替代方案,解释了文献和复合体之间接近的必要性.
- 需要对既有模型进行重新评估,考虑较旧,经常被忽视的文献.
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