Department of Plant Physiology, University of Umeå, S-901 87, Umeå, Sweden.
Photosynth Res. 1995 Nov;46(1-2):151-8. doi: 10.1007/BF00020425.
In this minireview we discuss effects of excitation stress on the molecular organization and function of PS II as induced by high light or low temperature in the cyanobacterium Synechococcus sp. PCC 7942. Synechococcus displays PS II plasticity by transiently replacing the constitutive D1 form (D1:1) with another form (D1:2) upon exposure to excitation stress. The cells thereby counteract photoinhibition by increasing D1 turn over and modulating PS II function. A comparison between the cyanobacterium Synechococcus and plants shows that in cyanobacteria, with their large phycobilisomes, resistance to photoinhibition is mainly through the dynamic properties (D1 turnover and quenching) of the reaction centre. In contrast, plants use antenna quenching in the light-harvesting complex as an important means to protect the reaction center from excessive excitation.
在这篇综述中，我们讨论了在蓝藻聚球藻 PCC 7942 中，高光或低温胁迫所引起的激发胁迫对 PSII 分子组成和功能的影响。聚球藻通过在暴露于激发胁迫时短暂地用另一种形式（D1:2）替代组成型 D1 形式（D1:1）来显示 PSII 可塑性。通过增加 D1 周转率和调节 PSII 功能，细胞从而抵抗光抑制。聚球藻与植物的比较表明，在含有大型藻胆体的蓝藻中，对光抑制的抗性主要是通过反应中心的动态特性（D1 周转率和猝灭）。相比之下，植物利用捕光复合物中的天线猝灭作为保护反应中心免受过度激发的重要手段。
