四川大学耿佳等研究人员合作利用功能化纳米孔实时检测20种氨基酸并分辨病理相关肽。2024年3月5日，《自然—方法学》杂志在线发表了该研究论文。

研究人员报告了一种具有N91H替换的铜(II)功能化耻垢分枝杆菌孔蛋白A（MspA）纳米孔，该纳米孔与机器学习算法相结合，可直接识别所有20个蛋白质氨基酸。验证准确率达到99.1%，信号恢复率为30.9%。该系统还证明了在纳摩尔范围内对氨基酸进行超灵敏定量的可行性。

此外，该系统还能利用外肽酶实时分析两种具有代表性的翻译后修饰（PTM）、一种非天然氨基酸和十种合成肽，包括与阿尔茨海默病和癌症新抗原相关的临床相关肽。值得注意的是，该策略成功地区分了与水解物只有一个氨基酸差异的肽，为推断肽序列提供了可能。

据介绍，氨基酸的精确鉴定和定量对许多生物应用至关重要。

附：英文原文

Title: Real-time detection of 20 amino acids and discrimination of pathologically relevant peptides with functionalized nanopore

Author: Zhang, Ming, Tang, Chao, Wang, Zichun, Chen, Shanchuan, Zhang, Dan, Li, Kaiju, Sun, Ke, Zhao, Changjian, Wang, Yu, Xu, Mengying, Dai, Lunzhi, Lu, Guangwen, Shi, Hubing, Ren, Haiyan, Chen, Lu, Geng, Jia

Issue&Volume: 2024-03-05

Abstract: Precise identification and quantification of amino acids is crucial for many biological applications. Here we report a copper(II)-functionalized Mycobacterium smegmatis porin A (MspA) nanopore with the N91H substitution, which enables direct identification of all 20 proteinogenic amino acids when combined with a machine-learning algorithm. The validation accuracy reaches 99.1%, with 30.9% signal recovery. The feasibility of ultrasensitive quantification of amino acids was also demonstrated at the nanomolar range. Furthermore, the capability of this system for real-time analyses of two representative post-translational modifications (PTMs), one unnatural amino acid and ten synthetic peptides using exopeptidases, including clinically relevant peptides associated with Alzheimer’s disease and cancer neoantigens, was demonstrated. Notably, our strategy successfully distinguishes peptides with only one amino acid difference from the hydrolysate and provides the possibility to infer the peptide sequence.

DOI: 10.1038/s41592-024-02208-7

Source: https://www.nature.com/articles/s41592-024-02208-7