Staehelin L A
Biochim Biophys Acta. 1975 Oct 10;408(1):1-11. doi: 10.1016/0005-2728(75)90153-x.
The supramolecular architecture of stacked thylakoid membrane regions of class II spinach chloroplasts has been investigated by means of freeze-fracture electron microscopy. Such membranes contain two basic types of intramembranous particles: laarge particles, which are found on the fracture face of the lumenal membrane leaflet (Bs face), and smaller ones which are found on the fracture face of the external leaflet (Cs face). By analyzing thylakoid membranes containing geometrical arrangements of intramembranous particles it is shown (a) that within the plane of each membrane approximately two small particles are associated with each large particle, and (b) that normal thylakoid stacking involves the connection of large particles of one membrane to small particles of the other and vice versa. If the two types of particles are related to Photosystems I and II, as suggested by circumstantial evidence, then our observations provide support for the idea that maximum Photosystem I-photosystem II interaction is obtained by intermembrane subunit interaction in grana stacks. To this end, our results suggest that stacking should enhance the quantum yield at very low light intensities.
通过冷冻蚀刻电子显微镜对II类菠菜叶绿体堆叠类囊体膜区域的超分子结构进行了研究。这类膜含有两种基本类型的膜内颗粒：大颗粒，位于类囊体腔面膜小叶的断裂面（Bs面）；小颗粒，位于外小叶的断裂面（Cs面）。通过分析含有膜内颗粒几何排列的类囊体膜发现：（a）在每个膜平面内，每个大颗粒大约与两个小颗粒相关联；（b）正常的类囊体堆叠涉及一个膜的大颗粒与另一个膜的小颗粒相连，反之亦然。如果如间接证据所暗示的，这两种类型的颗粒与光系统I和光系统II相关，那么我们的观察结果支持了这样一种观点，即通过基粒堆叠中的膜间亚基相互作用可实现光系统I - 光系统II的最大相互作用。为此，我们的结果表明，堆叠应能提高极低光强下的量子产率。
