Tateishi-Karimata Hisae, Pramanik Smritimoy, Sugimoto Naoki
Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-minamachi, Kobe 650-0047, Japan.
Analyst. 2015 Jul 7;140(13):4393-8. doi: 10.1039/c5an00545k.
The thermodynamic stability of certain mismatched base pairs has made the development of DNA sequence sensing systems challenging. Thus, the stability of fully matched and mismatched DNA oligonucleotides in the hydrated ionic liquid choline dihydrogen phosphate (choline dhp) was investigated. Mismatched base pairs were significantly destabilized in choline dhp relative to those in aqueous buffer. A molecular beacon that forms a triplex with a conserved HIV-1 sequence was then designed and tested in choline dhp. The molecular beacon specifically detected the target duplex via triplex formation at concentrations as low as 1 pmol per 10 μL with 10,000-fold sequence selectivity. Moreover, the molecular beacon was protected from a contaminating nuclease in choline dhp, and DNAs in aqueous solutions were not sufficiently stable for practical use.
某些错配碱基对的热力学稳定性给DNA序列传感系统的开发带来了挑战。因此，研究了完全匹配和错配的DNA寡核苷酸在水合离子液体磷酸二氢胆碱（胆碱dhp）中的稳定性。相对于在水性缓冲液中的错配碱基对，胆碱dhp中的错配碱基对明显不稳定。然后设计了一种与保守的HIV-1序列形成三链体的分子信标，并在胆碱dhp中进行了测试。该分子信标通过三链体形成以低至每10μL 1 pmol的浓度特异性检测目标双链体，具有10000倍的序列选择性。此外，胆碱dhp中的分子信标免受污染核酸酶的影响，而水溶液中的DNA对于实际应用来说稳定性不足。
