Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka Suita, Osaka, 565-0871, Japan.
Faculty of Pharmaceutical Sciences, Tokushima Bunri University, 180 Nishihamahoji, Yamashiro-cho, Tokushima, 770-8514, Japan.
Chemistry. 2021 Feb 19;27(11):3842-3848. doi: 10.1002/chem.202004819. Epub 2021 Jan 25.
Metal-mediated base pairs have widespread applications, such as in DNA-metal nanodevices and sensors. Here, we focused on their sugar conformation in duplexes and observed the crystallographic structure of the non-canonical DNA/DNA duplex containing 2'-O,4'-C-methylene bridged nucleic acid in the presence of Ag ions. The X-ray crystallographic structure was successfully obtained at a resolution of 1.5 Å. A novel type of Ag -mediated base pair between the N1 positions of anti-conformation of adenines in the duplex was observed. In the central non-canonical region, a hexad nucleobase structure containing Ag -mediated base pairs between the N7 positions of guanines was formed. A highly bent non-canonical structure was formed at the origin of Ag -mediated base pairs in the central region. The bent duplex structure induced by the addition of Ag ions might become a powerful tool for dynamic structural changes in DNA nanotechnology applications.
金属介导的碱基对具有广泛的应用，例如在 DNA-金属纳米器件和传感器中。在这里，我们专注于它们在双链体中的糖构象，并观察了在存在银离子的情况下含有 2'-O，4'-C-亚甲基桥接核酸的非规范 DNA/DNA 双链体的晶体结构。在 1.5 Å 的分辨率下成功获得了 X 射线晶体结构。在双链体中反构构象的腺嘌呤的 N1 位置之间观察到了一种新型的 Ag 介导的碱基对。在中心非规范区域中，形成了包含在鸟嘌呤的 N7 位置之间的 Ag 介导的碱基对的六聚体碱基结构。在中央区域 Ag 介导的碱基对的起源处形成了高度弯曲的非规范结构。由添加银离子引起的弯曲双链体结构可能成为 DNA 纳米技术应用中动态结构变化的有力工具。
