Roach Thomas, Krieger-Liszkay Anja
CEA Saclay, iBiTec-S, Bât. 532, 91191 Gif-sur-Yvette Cedex, France.
Curr Protein Pept Sci. 2014;15(4):351-62. doi: 10.2174/1389203715666140327105143.
Photosynthetic organisms and isolated photosystems are of interest for technical applications. In nature, photosynthetic electron transport has to work efficiently in contrasting environments such as shade and full sunlight at noon. Photosynthetic electron transport is regulated on many levels, starting with the energy transfer processes in antenna and ending with how reducing power is ultimately partitioned. This review starts by explaining how light energy can be dissipated or distributed by the various mechanisms of non-photochemical quenching, including thermal dissipation and state transitions, and how these processes influence photoinhibition of photosystem II (PSII). Furthermore, we will highlight the importance of the various alternative electron transport pathways, including the use of oxygen as the terminal electron acceptor and cyclic flow around photosystem I (PSI), the latter which seem particularly relevant to preventing photoinhibition of photosystem I. The control of excitation pressure in combination with the partitioning of reducing power influences the light-dependent formation of reactive oxygen species in PSII and in PSI, which may be a very important consideration to any artificial photosynthetic system or technical device using photosynthetic organisms.
光合生物和分离的光系统在技术应用方面具有重要意义。在自然界中，光合电子传递必须在诸如阴凉处和中午的全日照等截然不同的环境中高效运行。光合电子传递在多个层面受到调控，从天线中的能量传递过程开始，到最终如何分配还原力结束。本综述首先解释光能如何通过非光化学猝灭的各种机制进行耗散或分配，包括热耗散和状态转换，以及这些过程如何影响光系统II（PSII）的光抑制。此外，我们将强调各种替代电子传递途径的重要性，包括使用氧气作为末端电子受体以及围绕光系统I（PSI）的循环流动，后者似乎与防止光系统I的光抑制特别相关。激发压力的控制与还原力的分配相结合，会影响PSII和PSI中活性氧的光依赖性形成，这对于任何使用光合生物的人工光合系统或技术设备而言可能是一个非常重要的考虑因素。
