Gruner S M, Barry D T, Reynolds G T
Biochim Biophys Acta. 1982 Sep 9;690(2):187-98. doi: 10.1016/0005-2736(82)90322-4.
Sequences of X-ray diffraction patterns were obtained from dehydrating, artificially oriented multilayers of isolated, bovine rod outer segment disks. A direct-phase analysis was applied to highly hydrated specimens to determine sequences of low resolution (approx. 30 A) electron density profiles of the disks as dehydration proceeded. The profiles were found to evolve smoothly as the multilayer lattice simultaneously shrank and became increasingly ordered. The bilayer profiles were largely invariant under dehydration and the evolution of the diffraction consistent with simple decreases in fluid spacings. The specimens were observed to phase separate into characteristic primary and a secondary lattices when the multi-layer became too dehydrated. The small unit cell size of the secondary lattice was suggestive of a lipid phase. Large changes in the diffraction patterns from phase separated specimens were observed upon bleaching of the specimen. The changes were consistent with a reversible disordering of the primary lattice.
从脱水的、人工定向的分离牛视杆外段盘多层膜中获得X射线衍射图案序列。对高度水合的标本进行直接相位分析，以确定随着脱水过程进行，盘的低分辨率（约30埃）电子密度分布序列。发现随着多层晶格同时收缩并变得越来越有序，这些分布会平滑演变。双层分布在脱水过程中基本不变，且衍射的演变与流体间距的简单减小一致。当多层膜脱水过度时，观察到标本相分离成特征性的主晶格和次晶格。次晶格的小晶胞尺寸表明存在脂质相。在标本漂白后，观察到相分离标本的衍射图案发生了很大变化。这些变化与主晶格的可逆无序一致。
