Mechanism of energy conversion is conserved in the complex I superfamily All expressions of life ultimately depend on energy derived from redox chemistry and photosynthesis. On page 257 of this issue, Schuller et al. (1) report the structure of photosynthetic complex I at atomic resolution. The authors have analyzed how the distinct NADH [reduced form of oxidized nicotinamide adenine dinucleotide (NAD+)] dehydrogenase subunit S (NdhS) facilitates electron transfer from ferredoxin, thereby establishing efficient cyclic electron flow around photosystem I. The findings add an important piece to the puzzle of deciphering the enigmatic mechanisms at work in the remarkable molecular machines of the complex I superfamily encompassing photosynthetic and respiratory complex I, as well as proton pumping hydrogenases. In combination with high resolution structures of respiratory complex I from bacteria (2), mitochondria (3–5), and membrane bound hydrogenase (6), it is now possible to trace the modular evolution and functional adaptations of the complex I superfamily at the atomic level.

中文翻译：

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古老的模块化机器的改编

能量转换机制在复合体 I 超家族中是守恒的。生命的所有表达最终都依赖于来自氧化还原化学和光合作用的能量。在本期第 257 页，Schuller 等人。(1) 以原子分辨率报告光合复合物 I 的结构。作者分析了独特的 NADH [氧化烟酰胺腺嘌呤二核苷酸 (NAD+) 的还原形式] 脱氢酶亚基 S (NdhS) 如何促进铁氧还蛋白的电子转移，从而在光系统 I 周围建立有效的循环电子流。这些发现为破译复杂 I 超家族的非凡分子机器中工作的神秘机制的难题，包括光合作用和呼吸复合物 I，以及质子泵氢化酶。