Aerolysin蛋白纳米孔道直接检测单个DNA碱基修饰

Direct Single-molecule Discrimination of Acetylene-linked Deoxyribonucleoside Triphosphates with an Aerolysin Nanopore

基于Aerolysin生物膜通道蛋白的纳米孔道电化学分析技术,因其高的电化学空间限域能力可实现超灵敏DNA单分子检测。本文利用单个Aerolysin纳米孔道在无需标记、无需扩增的条件下直接分辨3种具有单个碱基差异的单链DNA。实验结果显示,具有单个炔基侧链基团修饰的单个ss DNA在限域空间内与Aerol-ysin纳米孔道的相互作用时间较未修饰的ss DNA增长近7倍,电流阻断程度增大7%,且高斯峰半峰宽减小了44%,增强了Aerolysin纳米孔道对单个DNA分子的分辨能力。研究成果有望推动Aerolysin纳米孔在DNA直接测序及表观遗传修饰检测中的应用。

Aerolysin could self-assemble and oligomerize heptameric complex which insert into the lipid bilayer to form a nanopore. Due to the electrochemically confined effects,the aerolysin shows the high sensitivity in single-molecule analysis of DNAs. Here,aerolysin was used to directly discriminate the single acetylene-linked deoxyribonucleoside triphosphates from a single oligonucleotide without label or PCR operations. After modifying with acetylene derivative,a single oligonucleotide produced seven times longer blockade duration inside an aerolysin nanopore,increasing the blockage current amplitude by 7% and narrowing the current distribution by 44%. Therefore,the modification of the linear side-chain of acetylene derivative could be further used to improve the temporal and spatial resolution in single DNA analysis via the aerolysin nanopore.