Nelson Nathan
Department of Biochemistry, The George S. Wise Faculty of Life Sciences, The Daniella Rich Institute for Structural Biology, Tel Aviv University, Tel Aviv 69978, Israel.
Biochim Biophys Acta. 2011 Aug;1807(8):856-63. doi: 10.1016/j.bbabio.2010.10.011. Epub 2010 Oct 16.
Because life on earth is governed by the second law of thermodynamics, it is subject to increasing entropy. Oxygenic photosynthesis, the earth's major producer of both oxygen and organic matter, is a principal player in the development and maintenance of life, and thus results in increased order. The primary steps of oxygenic photosynthesis are driven by four multi-subunit membrane protein complexes: photosystem I, photosystem II, cytochrome b(6)f complex, and F-ATPase. Photosystem II generates the most positive redox potential found in nature and thus capable of extracting electrons from water. Photosystem I generates the most negative redox potential found in nature; thus, it largely determines the global amount of enthalpy in living systems. The recent structural determination of PSII and PSI complexes from cyanobacteria and plants sheds light on the evolutionary forces that shaped oxygenic photosynthesis. This newly available structural information complements knowledge gained from genomic and proteomic data, allowing for a more precise description of the scenario in which the evolution of life systems took place. This article is part of a Special Issue entitled: Regulation of Electron Transport in Chloroplasts.
由于地球上的生命受热力学第二定律支配，因此会面临熵增的问题。产氧光合作用是地球氧气和有机物的主要生产者，在生命的发展和维持中起着主要作用，从而导致秩序增加。产氧光合作用的主要步骤由四种多亚基膜蛋白复合物驱动：光系统I、光系统II、细胞色素b(6)f复合物和F-ATP酶。光系统II产生自然界中发现的最正的氧化还原电位，因此能够从水中提取电子。光系统I产生自然界中发现的最负的氧化还原电位；因此，它在很大程度上决定了生命系统中的全球焓值。最近对蓝细菌和植物的光系统II和光系统I复合物的结构测定揭示了塑造产氧光合作用的进化力量。这些新获得的结构信息补充了从基因组和蛋白质组数据中获得的知识，从而能够更精确地描述生命系统进化发生的情景。本文是名为：叶绿体中电子传递的调控的特刊的一部分。
