作者:Jennifer Tuma、William H. Connors、David H. Stitelman、Clemens Richert
DOI:10.1021/ja0125117
日期:2002.4.1
demonstrated for all quinolones tested, namely nalidixic acid, oxolinic acid, pipemidic acid, cinoxacin, norfloxacin, and ofloxacin. The three-dimensional structure of (oa-T*GCGCA)2, where oa is an oxolinic acid residue, was solved by two-dimensional NMR spectroscopy and restrained molecular dynamics. In this complex, the oxolinic acid residues disrupt the terminal T1:A6 base pairs and stack on the G2:C5 base
喹诺酮类是促旋酶抑制剂,临床上广泛用作抗生素。当作为 5'-酰氨基取代基共价连接到寡核苷酸时,发现喹诺酮类可以稳定寡核苷酸的双链体,防止热变性。对于短双链体,例如 qu-T*GCGCA,其中 qu 是喹诺酮类残基,T 是 5'-amino-5'-deoxythymidine 残基,测量到的 UV 熔点升高高达 27.8 摄氏度。对所有测试的喹诺酮类,即萘啶酸、奥唑啉酸、哌啶酸、西诺沙星、诺氟沙星和氧氟沙星都证明了稳定作用。(oa-T*GCGCA)2 的三维结构,其中 oa 是恶啉酸残基,通过二维核磁共振光谱和约束分子动力学求解。在这个复合物中,恶唑酸残基破坏了末端 T1:A6 碱基对并堆叠在 G2:C5 碱基对上。被置换的腺苷残基结合在核心双链体的小沟中,而胸苷残基则与恶唑酸残基结合。如此形成的“分子帽”与 G:C 碱基对紧密贴合,从而提高了碱基配对保真度,如使用序列 oa-T*GGTTGAC