title: Chirality-assisted ring-like aggregation of aβ(1-40) at liquid-solid interfaces: a stereoselective two-step assembly process.
abstract: Molecular chirality is introduced at liquid-solid interfaces. A ring-like aggregation of amyloid Aβ(1-40) on N-isobutyryl-L-cysteine (L-NIBC)-modified gold substrate occurs at low Aβ(1-40) concentration, while D-NIBC modification only results in rod-like aggregation. Utilizing atomic force microscope controlled tip-enhanced Raman scattering, we directly observe the secondary structure information for Aβ(1-40) assembly in situ at the nanoscale. D- or L-NIBC on the surface can guide parallel or nonparallel alignment of β-hairpins through a two-step process based on electrostatic-interaction-enhanced adsorption and subsequent stereoselective recognition. Possible electrostatic interaction sites (R5 and K16) and a chiral recognition site (H14) of Aβ(1-40) are proposed, which may provide insight into the understanding of this effect.
authors.affiliation: State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (PR China).
authors.forename: Guanbin
authors.initials: G
authors.lastname: Gao
authors.forename: Mingxi
authors.initials: M
authors.lastname: Zhang
authors.forename: Pei
authors.initials: P
authors.lastname: Lu
authors.forename: Guanlun
authors.initials: G
authors.lastname: Guo
authors.forename: Dong
authors.initials: D
authors.lastname: Wang
authors.forename: Taolei
authors.initials: T
authors.lastname: Sun
mesh_terms: D016229:Amyloid beta-Peptides / Q000737:chemistry* / Q000648:ultrastructure; D003545:Cysteine / Q000031:analogs & derivatives / Q000737:chemistry; D006046:Gold / Q000737:chemistry; D006801:Humans; D018625:Microscopy, Atomic Force; D010446:Peptide Fragments / Q000737:chemistry* / Q000648:ultrastructure; D066329:Protein Aggregates; D017433:Protein Structure, Secondary; D055672:Static Electricity; D013237:Stereoisomerism; D013499:Surface Properties
chemical_list: D016229:Amyloid beta-Peptides; D010446:Peptide Fragments; D066329:Protein Aggregates; C078592:amyloid beta-protein (1-40); C096972:N-isobutyrylcysteine; D006046:Gold; D003545:Cysteine
keywords: amyloids; chirality; stereoselectivity; surface assembly; surface interactions