The OCU Advanced Research Institute for Natural Science & Technology (OCARINA), Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka City, Osaka, 558-8585, Japan.
Division of Environmental Photobiology, National Institute for Basic Biology, Nishigonaka 38, Myodaiji, Okazaki, 444-8585, Japan.
Photosynth Res. 2019 Nov;142(2):195-201. doi: 10.1007/s11120-019-00669-y. Epub 2019 Sep 6.
Light-harvesting complex II (LHCII) absorbs light energy and transfers it primarily to photosystem II in green algae and land plants. Although the trimeric structure of LHCII is conserved between the two lineages, its subunit composition and function are believed to differ significantly. In this study, we purified four LHCII trimers from the green alga Chlamydomonas reinhardtii and analyzed their biochemical properties. We used several preparation methods to obtain four distinct fractions (fractions 1-4), each of which contained an LHCII trimer with different contents of Type I, III, and IV proteins. The pigment compositions of the LHCIIs in the four fractions were similar. The absorption and fluorescence spectra were also similar, although the peak positions differed slightly. These results indicate that this green alga contains four types of LHCII trimer with different biochemical and spectroscopic features. Based on these findings, we discuss the function and structural organization of green algal LHCII antennae.
捕光复合物 II（LHCII）吸收光能，并将其主要转移到绿藻和陆地植物的光系统 II 中。尽管 LHCII 的三聚体结构在这两个谱系中是保守的，但它的亚基组成和功能据信有很大的不同。在这项研究中，我们从绿藻莱茵衣藻中纯化了四种 LHCII 三聚体，并分析了它们的生化特性。我们使用了几种制备方法来获得四种不同的馏分（馏分 1-4），每个馏分都含有一种具有不同含量的 I 型、III 型和 IV 型蛋白的 LHCII 三聚体。这四个馏分中的 LHCII 的色素组成相似。吸收和荧光光谱也相似，尽管峰位略有不同。这些结果表明，这种绿藻含有四种具有不同生化和光谱特征的 LHCII 三聚体。基于这些发现，我们讨论了绿藻 LHCII 天线的功能和结构组织。
