Accurate protein crystallography at ultra-high resolution: Valence electron distribution in crambin
Accurate protein crystallography at ultra-high resolution: Valence electron distribution in crambin
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DOI：
10.1073/pnas.97.7.3171
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发表时间：
2000-03-28
影响因子：
11.1
通讯作者：
Lecomte, C
中科院分区：
文献类型：
--
作者：
Jelsch, C;Teeter, MM;Lecomte, C
对蛋白质的电荷密度分布进行了实验研究。利用短波长同步辐射，在两个温度下测量了克拉姆宾晶体的超高分辨率(0.54埃)的衍射数据。晶体结构采用带电、非球形、多极原子模型来精确描述分子电子密度分布。改进后的参数与我们从几种氨基酸和小肽的精确单晶衍射分析中得到的可转移电子密度库符合25%以内，所得到的重新分布价电子的电子密度图(形变图)与对单肽进行的高水平量子力学计算在定量上是一致的。这项研究为实验得出的参数提供了验证，并为生物大分子的电荷密度分析提供了一个窗口。
The charge density distribution of a protein has been refined experimentally. Diffraction data for a crambin crystal were measured to ultra-high resolution (0.54 Angstrom) at tow temperature by using short-wavelength synchrotron radiation. The crystal structure was refined with a model for charged, nonspherical, multipolar atoms to accurately describe the molecular electron density distribution. The refined parameters agree within 25% with our transferable electron density library derived from accurate single crystal diffraction analyses of several amino acids and small peptides, The resulting electron density maps of redistributed valence electrons (deformation maps) compare quantitatively well with a high-level quantum mechanical calculation performed on a monopeptide. This study provides validation for experimentally derived parameters and a window into charge density analysis of biological macromolecules.