Dauter Zbigniew
Synchrotron Radiation Research Section, MCL, National Cancer Institute, Argonne National Laboratory, Argonne, IL 60439, USA.
Acta Crystallogr D Biol Crystallogr. 2013 May;69(Pt 5):872-8. doi: 10.1107/S0907444913002722. Epub 2013 Apr 19.
There are currently no rules for a unified, standard way of placing macromolecular structures in the crystal lattice. An analysis of all possible symmetry-equivalent representations of molecular structures in various space groups leads to the concept of the anti-Cheshire symmetry and suggests that the center of a unique structural motif can always be placed within the selected asymmetric unit of the anti-Cheshire cell. The placement of structures according to this suggestion will ensure uniformity of presentation of all structurally equivalent Protein Data Bank models and will therefore diminish the possibility of confusing less crystallographically knowledgeable users of the PDB. The anti-Cheshire cells and their asymmetric units are defined and tabulated for all 65 space groups relevant to macromolecular crystallography that exhibit only rotational symmetry operations.
目前尚无关于在晶格中放置大分子结构的统一、标准方法的规则。对各种空间群中分子结构的所有可能对称等效表示进行分析，得出了反柴郡对称的概念，并表明独特结构基序的中心总能放置在反柴郡晶胞选定的不对称单元内。按照这一建议放置结构将确保所有结构等效的蛋白质数据库模型呈现的一致性，从而减少让对晶体学了解较少的蛋白质数据库用户产生混淆的可能性。针对大分子晶体学相关的所有65种仅表现出旋转对称操作的空间群，定义并列出了反柴郡晶胞及其不对称单元。
