Lebedev Andrey A, Vagin Alexei A, Murshudov Garib N
Structural Biology Laboratory, Department of Chemistry, University of York, Heslington, York YO10 5YW, England.
Acta Crystallogr D Biol Crystallogr. 2008 Jan;64(Pt 1):33-9. doi: 10.1107/S0907444907049839. Epub 2007 Dec 5.
The success of molecular replacement is critically dependent on the quality of the search model. Several model-preparation procedures are integrated in the molecular-replacement program MOLREP. These include model modification on the basis of amino-acid sequence alignment and model correction based on analysis of the solvent-accessibility of the atoms. The packing function used in MOLREP for the translational search is explained in the context of model preparation. In difficult cases, bioinformatics-based modifications are not sufficient for successful molecular replacement. An approach implemented in MOLREP for solving cases with translational noncrystallographic symmetry is an example of model preparation in which analysis of X-ray data plays an essential role. In addition, two examples are presented in which the X-ray data were used to refine partial models for subsequent use in molecular replacement.
分子置换的成功与否关键取决于搜索模型的质量。分子置换程序MOLREP中集成了多种模型制备程序。这些程序包括基于氨基酸序列比对的模型修正以及基于原子溶剂可及性分析的模型校正。在模型制备的背景下解释了MOLREP中用于平移搜索的堆积函数。在困难的情况下，基于生物信息学的修正不足以实现成功的分子置换。MOLREP中用于解决具有平移非晶体学对称性情况的一种方法是模型制备的一个例子，其中X射线数据的分析起着至关重要的作用。此外，还给出了两个例子，其中利用X射线数据对部分模型进行精修，以供后续分子置换使用。
