Navia M A, Segal D M, Padlan E A, Davies D R, Rao N, Rudikoff S, Potter M
Proc Natl Acad Sci U S A. 1979 Aug;76(8):4071-4. doi: 10.1073/pnas.76.8.4071.
An electron-density map of the mouse galactan-binding immunoglobulin J539 (IgA2,kappa) Fab has been calculated to a resolution of 4.5 A by the method of heavy atom isomorphous replacement with four derivatives. The map has been interpreted with the aid of a computer program which systematically searched for the best fit between the electron-density map and the known coordinates of individual immunoglobulin domains. The quaternary structure of J539 Fab at this resolution appears similar to that of another mouse immunoglobulin, IgA2,kappa Fab, McPC603. The model coordinates for J539 Fab should allow us to proceed directly to a high-resolution structure determination without further heavy atom isomorphous replacement.
通过四个衍生物的重原子同晶置换法，已计算出小鼠半乳糖结合免疫球蛋白J539（IgA2，κ）Fab的电子密度图，分辨率为4.5埃。借助计算机程序对该图进行了解释，该程序系统地搜索了电子密度图与各个免疫球蛋白结构域已知坐标之间的最佳匹配。在此分辨率下，J539 Fab的四级结构似乎与另一种小鼠免疫球蛋白IgA2，κ Fab McPC603相似。J539 Fab的模型坐标应使我们能够直接进行高分辨率结构测定，而无需进一步进行重原子同晶置换。
