Schiffer M, Edmundson A B
Biophys J. 1968 Jan;8(1):29-39. doi: 10.1016/S0006-3495(68)86472-0.
Correlation of the amino acid sequence with the conformation in tobacco mosaic virus protein is considered in this article. After division of the sequence into groups with helical or nonhelical potential, the segments likely to be helical were related to the X-ray diffraction patterns obtained by Franklin, Caspar, Holmes, and Klug. The approximate locations of these segments within the known boundaries of the subunit were predicted from the radial distribution and helical projection of electron density. As a result of these assignments, the number of possible conformations was also reduced for the nonhelical segments. The structure of the subunit was simulated by flexible models of rubber and electrical tubing, as well as by space-filling Corey-Pauling-Koltun models. These models were used to locate the protein segments impinging upon the ribonucleic acid of the virus. The two pairs of carboxyl groups believed to be responsible for the binding of lead were also tentatively identified on these models as aspartic acid residues 64 and 66 (first pair) and glutamic acid residues 131 and 145 (second pair).
本文探讨了烟草花叶病毒蛋白质中氨基酸序列与构象的相关性。在将序列分为具有螺旋或非螺旋潜力的组之后，可能呈螺旋状的片段与富兰克林、卡斯帕、霍姆斯和克鲁格获得的X射线衍射图谱相关联。根据电子密度的径向分布和螺旋投影，预测了这些片段在亚基已知边界内的大致位置。这些分配的结果是，非螺旋片段的可能构象数量也减少了。通过橡胶和电线管的柔性模型以及空间填充的科里-鲍林-科尔图恩模型对亚基的结构进行了模拟。这些模型用于定位与病毒核糖核酸相互作用的蛋白质片段。在这些模型上，也初步确定了被认为负责结合铅的两对羧基，分别为天冬氨酸残基64和66（第一对）以及谷氨酸残基131和145（第二对）。
