Reconstitution of lypophilic components in Photosystem I complex which had been extracted with diethyl ether

用乙醚萃取的光系统 I 复合物中亲脂性成分的重构

基本信息

批准号：
15570040
负责人：
IKEGAMI Isamu
金额：
$ 2.5万
依托单位：
Teikyo University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2003
资助国家：
日本
起止时间：
2003 至 2005
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15570040/
关键词：
Photosynthesis Photosystem I Photosynthetic Reaction center Chlorophyll P700

项目摘要

1.Chlorophylls, such as Chl b, Chl a epimer and Phe a, all which do not act as intrinsic antenna in the PSI RC complex, were added with phosphatidylglycerol to the antenna-depleted PSI complex that had a Chl a/P700 ratio of 12. We found that the Chl a-binding site allows to receive Chl b with the same affinity as Chl a, but Chl a epimer with the affinity half of Chl a. The bound Chl b and Chl a epimer act as efficient antenna as Chl a. Phe a binds the antenna-depleted PSI complex, but without any efficient transfer of light energy to P700. We conclude that Chl a-binding site is tolerable to Chl with a side-chain different from Chl a, showing lower affinity with a large structural difference, and that Mg is essential to bind the site.2.Chlorella, when grown in the dark with an extremely high concentration of Zn, formed Zn-Chl a in amount of about 30% of Chl a. We found that the Zn-Chl a binds to PSI and PSII RC complexes and acts as efficient antenna as Mg-Chl a.3.PSI complex isolated from phylloquinone-depleted mutant of Arabidopsis, had no P700 but emitted the far red fluorescence at 77K which is characteristic to PSI antenna. We suggest that it had a PSI complex with antenna Chl a but without PSI electron carriers such as P700 and A_0.

1.Chlorophylls, such as Chl b, Chl a epimer and Phe a, all which do not act as intrinsic antenna in the PSI RC complex, were added with phosphatidylglycerol to the antenna-depleted PSI complex that had a Chl a/P700 ratio of 12. We found that the Chl a-binding site allows to receive Chl b with the same affinity as Chl a, but Chl a epimer with chl a的亲和力一半。绑定的Chl B和Chl A Eximer作用与Chl a一样有效的天线。 PHE A结合了耗尽天线的PSI复合物，但没有任何有效的光能转移到P700。我们得出的结论是，CHL A结合位点在CHL上可以耐受性链，其侧链与CHL A不同，显示出较大的结构差异，并且MG对于结合位点的粘合至关重要。2.Chlorella在黑暗中以极高的Zn浓度生长，形成Zn-CHL，以Zn-Chl形成大约30％的Chl A A。我们发现，Zn-CHL A与PSI和PSII RC复合物结合，并且与Mg-Chl A.3.PSI复合物的有效天线相结合，从拟南芥的phylloquinone耗尽的突变体中分离出来，但没有P700，但没有PSI天线的77K发射型红色荧光。我们建议它具有带有天线CHL A的PSI复合物，但没有PSI电子载体，例如P700和A_0。