法国塞吉-蓬图瓦兹大学Abdelghani Oukhaled、美国伊利诺伊大学厄巴纳-香槟分校Aleksei Aksimentiev等研究人员合作利用气溶素纳米孔对20种蛋白质氨基酸进行电识别。该项研究成果在线发表在2019年12月16日的《自然—生物技术》上。

研究人员报道了借助于短聚阳离子载体对气溶素纳米孔中所有二十种蛋白氨基酸的离子电流检测技术。分子动力学模拟的应用表明，气溶素纳米孔具有内置的单分子阱，其将聚阳离子载体结合的氨基酸完全限制在气溶素的感应区内。这种结构特征意味着每种氨基酸在孔中花费足够的时间来敏感地测量氨基酸的排除体积。研究人员发现，野生型气溶素中不同的电流屏障可用于识别20个天然氨基酸中的13个。此外，研究人员表明化学修饰、仪器的进步和纳米孔工程技术为鉴定剩余的七种氨基酸提供了一条途径。这些发现可能为纳米孔蛋白测序铺平了道路。

据了解，利用纳米孔对单个蛋白质分子进行测序的工作由于缺乏足够的灵敏度来分辨所有二十种氨基酸之间细微的分子差异而受到阻碍。

附：英文原文

Title: Electrical recognition of the twenty proteinogenic amino acids using an aerolysin nanopore

Author: Hadjer Ouldali, Kumar Sarthak, Tobias Ensslen, Fabien Piguet, Philippe Manivet, Juan Pelta, Jan C. Behrends, Aleksei Aksimentiev, Abdelghani Oukhaled

Issue&Volume: 2019-12-16

Abstract: Efforts to sequence single protein molecules in nanopores1,2,3,4,5 have been hampered by the lack of techniques with sufficient sensitivity to discern the subtle molecular differences among all twenty amino acids. Here we report ionic current detection of all twenty proteinogenic amino acids in an aerolysin nanopore with the help of a short polycationic carrier. Application of molecular dynamics simulations revealed that the aerolysin nanopore has a built-in single-molecule trap that fully confines a polycationic carrier-bound amino acid inside the sensing region of the aerolysin. This structural feature means that each amino acid spends sufficient time in the pore for sensitive measurement of the excluded volume of the amino acid. We show that distinct current blockades in wild-type aerolysin can be used to identify 13 of the 20 natural amino acids. Furthermore, we show that chemical modifications, instrumentation advances and nanopore engineering offer a route toward identification of the remaining seven amino acids. These findings may pave the way to nanopore protein sequencing.

DOI: 10.1038/s41587-019-0345-2

Source: https://www.nature.com/articles/s41587-019-0345-2