Direct observation of protein solvation and discrete disorder with experimental crystallographic phases
Direct observation of protein solvation and discrete disorder with experimental crystallographic phases
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DOI：
10.1126/science.271.5245.72
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发表时间：
1996-01-05
期刊：
影响因子：
56.9
通讯作者：
Brunger, AT
中科院分区：
文献类型：
--
作者：
Burling, FT;Weis, WI;Brunger, AT
一个完整的和准确的实验结晶相的分辨率为1.8埃，获得了230个残基的二聚体片段的大鼠甘露糖结合蛋白A与使用多波长异常色散（MAD）定相。因此，可以获得晶体结构的精确图像，而无需求助于从模型计算的相位。部分还原的二硫键，局部无序，和化学等效分子的流动性差异是明显的实验电子密度图。溶剂化层是可见的，其包括围绕极性和带电蛋白质原子的有序的水合位点，以及围绕暴露的疏水基团的扩散的、部分无序的溶剂壳。由于实验阶段和由此产生的电子密度图是免费的模型的影响，它们提供了一个严格的测试大分子溶剂化，运动和构象异质性的理论模型。
A complete and accurate set of experimental crystallographic phases to a resolution of 1.8 angstroms was obtained for a 230-residue dimeric fragment of rat mannose-binding protein A with the use of multiwavelength anomalous dispersion (MAD) phasing. An accurate image of the crystal structure could thus be obtained without resort to phases calculated from a model. Partially reduced disulfide bonds, local disorder, and differences in the mobility of chemically equivalent molecules are apparent in the experimental electron density map. A solvation layer is visible that includes well-ordered sites of hydration around polar and charged protein atoms, as well as diffuse, partially disordered solvent shells around exposed hydrophobic groups. Because the experimental phases and the resulting electron density map are free from the influence of a model, they provide a stringent test of theoretical models of macromolecular solvation, motion, and conformational heterogeneity.