Seino Takehiro, Nishizawa Seiichi, Teramae Norio
Department of Chemistry, Graduate School of Science, Tohoku University, Aoba-ku, Sendai 980-8578, Japan.
Nucleic Acids Symp Ser (Oxf). 2005(49):205-6. doi: 10.1093/nass/49.1.205.
Here we report on the strong and selective binding of a hydrogen bond-forming ligand, 2-amino-7-methyl-1,8-naphthyridine (AMND), to a nucleobase at a gap site in DNA duplexes. In solutions buffered to pH 7.0 (at 20 degrees C, I = 0.11 M), AMND is found to selectively recognize cytosine (C) base over other nucleotides, and the 1:1 association constant reaches 3.2x10(5) M(-1) when binding to C. The ligand-nucleotide interaction results in significant fluorescence quenching of AMND, which is highly selective to C. These sensing functions of AMND at the gap site are utilized for the development of ligand-based fluorescence assay for SNPs (single-nucleotide polymorphisms) typing.
在此，我们报道了一种形成氢键的配体2-氨基-7-甲基-1,8-萘啶（AMND）与DNA双链体间隙位点处的核碱基之间的强选择性结合。在pH 7.0缓冲溶液中（20℃，I = 0.11 M），发现AMND相对于其他核苷酸能选择性识别胞嘧啶（C）碱基，与C结合时1:1缔合常数达到3.2×10⁵ M⁻¹。配体 - 核苷酸相互作用导致AMND显著的荧光猝灭，且对C具有高度选择性。AMND在间隙位点的这些传感功能被用于开发基于配体的单核苷酸多态性（SNP）分型荧光测定法。
