Neutron Crystallographic study of hydration structures of DNA and its fluctuation

为了揭示DNA水化的结构，包括结构波动，进行了中子和x射线晶体学研究。(1)可生成氘化Z-DNA d（CGCGCG）。(2)从H2O溶液中获得了Z-DNA d（CGCGCG）大单晶，并利用脉冲中子源进行了TOF中子实验。在1.6 ~ 1.8埃范围内检测到中子衍射斑点。使用蛋白质晶体的中子数据集对改进方案进行了测试。同时进行了x射线晶体学分析，测定了高、低浓度金属盐下的Z-DNA结构。这些结构中的每一个都有特定的特征，这表明这些晶体将是中子晶体学研究的主要候选者。

For the purpose of revealing structure of DNA hydration including structural fluctuation, neutron and X-ray crystallographic studies were carried out. (1) Deuterated Z-DNA d(CGCGCG) could be produced. (2) Large single crystals of Z-DNA d(CGCGCG) were obtained from H2O solution, and TOF neutron experiment was performed using pulsed neutron source. Neutron diffraction spots were detected up to 1.6 -1.8 Angstrom. Protocol for refinements was tested using neutron data sets of protein crystals. X-ray crystallographic analyses were also carried out complementarily, as the result, Z-DNA structures at high and low concentrations of metal salts were determined. Each of these structures had specific features, suggesting that these crystals would be dominant candidates for neutron crystallographic studies.