Wood A A, Nunn C M, Trent J O, Neidle S
The CRC Biomolecular Structure Unit, The Institute of Cancer Research, Sutton, Surrey, UK.
J Mol Biol. 1997 Jun 27;269(5):827-41. doi: 10.1006/jmbi.1997.1089.
The structure of the B-DNA decamer d(CGCAATTGCG)2 has been determined by X-ray diffraction analysis to a resolution of 2.3 A and an R-factor of 17.7%. The decamer crystallises in the monoclinic space group C2 and packs with a crossed arrangement of helices and a unique crossing contact distinct from all other decamer structures. This is believed to be a direct result of the sequence-dependent minor groove width of the duplex. Crossed helix structures of DNA are valuable starting points for modelling studies of the Holliday junction. Two unique sites are observed at the cross-over junction where strand exchange may occur. A Holliday junction model has been constructed for each case and modelled using molecular mechanics and dynamics techniques. One of these models was found to be fully consistent with the available physical data.
已通过X射线衍射分析确定了B型DNA十聚体d(CGCAATTGCG)₂的结构，分辨率为2.3埃，R因子为17.7%。该十聚体在单斜空间群C2中结晶，以螺旋的交叉排列堆积，并且具有与所有其他十聚体结构不同的独特交叉接触。据信这是双链体序列依赖性小沟宽度的直接结果。DNA的交叉螺旋结构是霍利迪连接体建模研究的重要起点。在交叉连接处观察到两个可能发生链交换的独特位点。针对每种情况构建了霍利迪连接体模型，并使用分子力学和动力学技术进行建模。发现其中一个模型与现有的物理数据完全一致。
