Structural variability, coordination and adaptation of a native photosynthetic machinery
Structural variability, coordination and adaptation of a native photosynthetic machinery
复制标题
DOI：
10.1038/s41477-020-0694-3
复制
发表时间：
2020-07
期刊：
影响因子：
18
通讯作者：
Long-Sheng Zhao;Tuomas Huokko;Sam Wilson;D. Simpson;Qiang Wang;A. Ruban;C. Mullineaux;Yu‐Zhong Zhang-Yu‐Zh
中科院分区：
文献类型：
--
作者：
Long-Sheng Zhao;Tuomas Huokko;Sam Wilson;D. Simpson;Qiang Wang;A. Ruban;C. Mullineaux;Yu‐Zhong Zhang-Yu‐Zh
蓝藻类囊体膜是光合作用和呼吸电子传递的活性部位。我们使用高分辨率原子力显微镜来可视化来自模型蓝藻细长聚球藻PCC7942的类囊体膜内光合作用复合体的自然组织和相互作用。类囊体膜是异质的，它将光合作用的复合体组装成功能区，以加强它们的协调和调节。在强光下，叶绿素结合蛋白isia强烈表达，并与光系统I(Psi)结合，形成高度可变的ISIA−Psi超复合体，增加Psi的吸收截面。PSI还与光系统II(PSII)、细胞色素b6f、ATP合成酶和NAD(P)H脱氢酶复合体有紧密的相互作用。这些光合作用超复合体的组织可变性允许有效的线性和循环电子传递以及生物能量调节。了解蓝藻类囊体膜的组织景观和环境适应性可能有助于为设计高效的光合作用系统和光生物工厂提供信息。
Cyanobacterial thylakoid membranes represent the active sites for both photosynthetic and respiratory electron transport. We used high-resolution atomic force microscopy to visualize the native organization and interactions of photosynthetic complexes within the thylakoid membranes from the model cyanobacteriumSynechococcus elongatusPCC 7942. The thylakoid membranes are heterogeneous and assemble photosynthetic complexes into functional domains to enhance their coordination and regulation. Under high light, the chlorophyll-binding proteins IsiA are strongly expressed and associate with Photosystem I (PSI), forming highly variable IsiA−PSI supercomplexes to increase the absorption cross-section of PSI. There are also tight interactions of PSI with Photosystem II (PSII), cytochromeb6f, ATP synthase and NAD(P)H dehydrogenase complexes. The organizational variability of these photosynthetic supercomplexes permits efficient linear and cyclic electron transport as well as bioenergetic regulation. Understanding the organizational landscape and environmental adaptation of cyanobacterial thylakoid membranes may help inform strategies for engineering efficient photosynthetic systems and photo-biofactories.