文献类型：期刊文献

英文题名：Rationally Designed Sensing Selectivity and Sensitivity of an Aerolysin Nanopore via Site-Directed Mutagenesis

作者：Wang, Ya-Qian[1,2];Cao, Chan[1,2];Ying, Yi-Lun[1,2];Li, Shuang[1,2];Wang, Ming-Bo[3];Huang, Jin[3];Long, Yi-Tao[1,2]

机构：[1]East China Univ Sci & Technol, Key Lab Adv Mat, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Sch Chem & Mol Engn, Shanghai 200237, Peoples R China;[3]East China Univ Sci & Technol, Sch Pharm, Shanghai 200237, Peoples R China

年份：2018

卷号：3

期号：4

起止页码：779

外文期刊名：ACS SENSORS

收录：;EI(收录号：20181805112485);WOS:【SCI-EXPANDED(收录号:WOS:000431165200007)】；

基金：This research was supported by the National Key R&D Program of China (2017YFC0906500), National Natural Science Foundation of China (21421004 and 21327807), the "Chen Guang" project from Shanghai Municipal Education Commission and Shanghai Education Development Foundation, and the Fundamental Research Funds for the Central Universities (222201718001, 222201717003, 222201714012).

语种：英文

外文关键词：selectivity; sensitivity; single molecule; aerolysin; nanosensor

摘要：Selectivity and sensitivity are two key parameters utilized to describe the performance of a sensor. In order to investigate selectivity and sensitivity of the aerolysin nanosensor, we manipulated its surface charge at different locations via single site-directed mutagenesis. To study the selectivity, we replaced the positively charged R220 at the entrance of the pore with negatively charged glutamic acid, resulting in barely no current blockages for sensing negatively charged oligonucleotides. For the sensitivity, we substituted the positively charged lumen-exposed amino acid K238 located at trans-ward third of the beta-barrel stem with glutamic acid. This leads to a surprisingly longer duration time at +140 mV, which is about 20 times slower in translocation speed for Poly(dA)(4) compared to that of wild-type aerolysin, indicating the stronger pore-analyte interactions and enhanced sensitivity. Therefore, it is both feasible and understandable to rationally design confined biological nanosensors for single molecule detection with high selectivity and sensitivity.