Department of Plant Physiology and Biochemistry, University of Konstanz, Universitätsstrasse 10, D-78457 Konstanz, Germany.
Res Microbiol. 2009 Nov;160(9):726-32. doi: 10.1016/j.resmic.2009.08.005. Epub 2009 Sep 2.
Organisms that perform oxygenic photosynthesis are subjected to photoinhibition of their photosynthetic function when exposed to excessive illumination. The main target of photoinhibition is the D1 protein in the reaction center of the photosystem II complex. Rapid degradation of photodamaged D1 protein and its replacement by a de novo synthesized functional copy represent an important repair mechanism crucial for cell survival under light stress conditions. This review summarizes the literature on the ATP-independent Deg/HtrA family of serine endopeptidases in cyanobacteria and chloroplasts of higher plants, and discusses their role in D1 protein degradation. We propose that Deg/HtrA proteases are part of a larger network of enzymes that ensure protein quality control, including photosystem II, in plants and cyanobacteria.
进行放氧光合作用的生物在暴露于过量光照时，其光合作用功能会受到光抑制。光抑制的主要靶标是光合系统 II 复合物反应中心的 D1 蛋白。光损伤的 D1 蛋白的快速降解及其被从头合成的功能副本取代，代表了在光胁迫条件下细胞存活的关键重要修复机制。本综述总结了关于蓝藻和高等植物叶绿体中 ATP 非依赖性 Deg/HtrA 丝氨酸内肽酶家族的文献，并讨论了它们在 D1 蛋白降解中的作用。我们提出，Deg/HtrA 蛋白酶是确保包括植物和蓝藻中的光合系统 II 在内的蛋白质质量控制的更大酶网络的一部分。
