title: Metal-organic complex-functionalized protein nanopore sensor for aromatic amino acids chiral recognition.
abstract: Chiral recognition at single-molecule level for small active molecules is important, as exhibited by many nanostructures and molecular assemblies in biological systems, but it presents a significant challenge. We report a simple and rapid sensing strategy to discriminate all enantiomers of natural aromatic amino acids (AAA) using a metal-organic complex-functionalized protein nanopore, in which a chiral recognition element and a chiral recognition valve were equipped. A trifunctional molecule, heptakis-(6-deoxy-6-amino)-β-cyclodextrin (am7βCD), was non-covalently lodged within the nanopore of an α-hemolysin (αHL) mutant, (M113R)7-αHL. Copper(ii) ion reversibly bonds to the amino group of am7βCD to form an am7βCD-CuIIcomplex, which allowed chiral recognition for each enantiomer in the mixture of AAA by distinct current signals. The CuIIplugging valve plays a crucial rule that holds chiral molecules in the nanocavity for a sufficient registering time. Importantly, six enantiomers of all nature AAA could be simultaneously recognized at one time. Enantiomeric excess (ee) could also be accurately detected by this approach. It should be possible to generalize this approach for sensing of other chiral molecules.
authors.affiliation: Key Laboratory of Synthetic and Natural Functional Molecular Chemistry, College of Chemistry & Materials Science, Northwest University, Xi'an 710069, P. R. China. kangxf@nwu.edu.cn.
authors.forename: Yanli
authors.initials: Y
authors.lastname: Guo
authors.affiliation: Key Laboratory of Synthetic and Natural Functional Molecular Chemistry, College of Chemistry & Materials Science, Northwest University, Xi'an 710069, P. R. China. kangxf@nwu.edu.cn.
authors.forename: Aihua
authors.initials: A
authors.lastname: Niu
authors.affiliation: Key Laboratory of Synthetic and Natural Functional Molecular Chemistry, College of Chemistry & Materials Science, Northwest University, Xi'an 710069, P. R. China. kangxf@nwu.edu.cn.
authors.forename: Feifei
authors.initials: F
authors.lastname: Jian
authors.affiliation: Key Laboratory of Synthetic and Natural Functional Molecular Chemistry, College of Chemistry & Materials Science, Northwest University, Xi'an 710069, P. R. China. kangxf@nwu.edu.cn.
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Key Laboratory of Synthetic and Natural Functional Molecular Chemistry, College of Chemistry & Materials Science, Northwest University, Xi'an 710069, P. R. China. kangxf@nwu.edu.cn.
authors.forename: Fujun
authors.initials: F
authors.lastname: Yao
authors.affiliation: Key Laboratory of Synthetic and Natural Functional Molecular Chemistry, College of Chemistry & Materials Science, Northwest University, Xi'an 710069, P. R. China. kangxf@nwu.edu.cn.
authors.forename: Yongfeng
authors.initials: Y
authors.lastname: Wei
authors.affiliation: Key Laboratory of Synthetic and Natural Functional Molecular Chemistry, College of Chemistry & Materials Science, Northwest University, Xi'an 710069, P. R. China. kangxf@nwu.edu.cn.
authors.forename: Lei
authors.initials: L
authors.lastname: Tian
authors.affiliation: Key Laboratory of Synthetic and Natural Functional Molecular Chemistry, College of Chemistry & Materials Science, Northwest University, Xi'an 710069, P. R. China. kangxf@nwu.edu.cn.
authors.forename: Xiaofeng
authors.identifier: http://orcid.org/0000-0002-2724-326X
authors.initials: X
authors.lastname: Kang