NEC Solution Innovators, Ltd, 1-18-7, Shinkiba, Koto-ku, 136-8627, Tokyo, Japan.
Graduate School of Integrated Basic Sciences, Nihon University, 3-25-40 Sakurajosui, Setagaya-ku, 156-8550, Tokyo, Japan.
Anal Biochem. 2020 Apr 1;594:113627. doi: 10.1016/j.ab.2020.113627. Epub 2020 Feb 15.
We used base-appended base modification to develop a new adenine analog, which incorporates an adenine derivative at position 7 of adenine. Using the systematic evolution of ligands by exponential enrichment method with a modified DNA library including this analog, we obtained A, an aptamer that binds strongly to human β-defensin 2, a biomarker of physical stress found in saliva. The dissociation constant of A with respect to human β-defensin 2 was found to be low (6.8 nM), and was found to bind specifically to human β-defensin 2 in saliva spiked with the protein, as confirmed using pull-down with magnetic beads. To our knowledge, there are no prior reports of nucleic-acid aptamers that bind specifically to human β-defensin 2. However, our results indicated that such adenine analog-containing DNA libraries are extremely effective in the acquisition of high-affinity aptamers.
我们使用碱基末端添加碱基修饰的方法开发了一种新的腺嘌呤类似物，它在腺嘌呤的第 7 位引入了腺嘌呤衍生物。使用含有这种类似物的经修饰 DNA 文库，通过指数富集配体系统进化方法，我们获得了 A，这是一种与人类 β-防御素 2（唾液中物理应激的生物标志物）结合能力很强的适体。A 与人 β-防御素 2 的解离常数较低（6.8 nM），并且在唾液中与人 β-防御素 2 特异性结合，这一点通过用磁性珠进行下拉实验得到了证实。据我们所知，尚无先前报道的能够特异性结合人类 β-防御素 2 的核酸适体。然而，我们的结果表明，含有这种腺嘌呤类似物的 DNA 文库在获得高亲和力适体方面非常有效。
