Boekema E J, Berden J A, van Heel M G
Biochim Biophys Acta. 1986 Oct 8;851(3):353-60. doi: 10.1016/0005-2728(86)90071-x.
The structure of soluble F1-ATPase (EC 3.6.1.3) has been investigated by computer analysis of individual molecular images extracted from electron micrographs of negatively stained particles. A total of 1241 images was interactively selected from several digitized micrographs and these images were subsequently aligned relative to different reference images. They were then submitted to a multivariate statistical classification procedure. We have focussed our attention on the main 'hexagonal' view which represents some 40% of our population of images. In this view, six masses are located on the outer region of the projection which are associated with the alpha and the beta subunits of the protein. A seventh mass is located close to the centre of the hexagon, but slightly off its exact midpoint. It has the shape of the letter V and its two legs point to two of the outer protein masses, or one alpha-beta subunit pair. The corner of the V has a density as high as those of the large subunits. Possible subunit arrangements and their consequences for the mechanism of ATP synthesis are discussed.
通过对从负染颗粒电子显微照片中提取的单个分子图像进行计算机分析，研究了可溶性F1 - ATP酶（EC 3.6.1.3）的结构。从几张数字化显微照片中交互式选择了总共1241张图像，随后将这些图像相对于不同的参考图像进行对齐。然后将它们提交给多变量统计分类程序。我们将注意力集中在主要的“六边形”视图上，该视图约占我们图像总数的40%。在此视图中，六个团块位于投影的外部区域，与蛋白质的α和β亚基相关。第七个团块位于六边形中心附近，但略偏离其精确中点。它呈字母V形，其两条腿指向两个外部蛋白质团块，或一对α - β亚基。V的角部密度与大亚基的密度一样高。讨论了可能的亚基排列及其对ATP合成机制的影响。
