在SHELXE的模式和模型建筑.
Isabel Usón1, George M Sheldrick2
1ICREA, Institució Catalana de Recerca i Estudis Avançats, Passeig Lluís Companys, 23, Barcelona, E-08003, Spain.
Acta crystallographica. Section D, Structural biology
|December 13, 2023
概括
密度修改改进了晶体电子密度图,通过实验分相来帮助结构解决. SHELXE程序的改进提高了模型构建和相位精度,以实现完整的结构确定.
科学领域:
- 晶体学 晶体学是指结晶学.
- 结构生物学 结构生物学
- 计算化学的计算化学
背景情况:
- 密度修改对于解决实验阶段化方法至关重要.
- 流行的方法包括单波长和多波长异常衍射.
- 它将部分模型和碎片扩展到完整的结构中.
研究的目的:
- 为了说明密度修改对使用SHELXE的起始地图的影响.
- 审查SHELXE计划的不同操作模式.
- 讨论用于完整模型构建的追踪算法的扩展.
主要方法:
- 使用密度修改来改善初始阶段集.
- 采用聚氨酸痕迹用于结构延伸.
- 实施模型偏差消除和序列对接.
- 使用亨德里克森-拉特曼系数分析相位分布.
主要成果:
- SHELXE程序的增强可以提高模型构建和相位精度.
- 追踪算法现在包括侧链配件的扩展.
- 一个相关系数值表明成功的结构解决方案.
- 密度修改有效地改进了电子密度图.
结论:
- SHELXE的密度修改和跟踪扩展方便了常规结构解决方案.
- 该程序提供高级功能,用于处理相位信息.
- 改进的算法可以提高分阶段性能,并完成模型构建.
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