3D Blockage Mapping for Identifying Familial Point Mutations in Single Amyloid‐β Peptides with a Nanopore
Kai‐Li Xin, Zheng‐Li Hu, Shao-Chuang Liu, Xinyi Li, Jun‐Ge Li, Hongyan Niu, Yi‐Lun Ying, Yi‐Tao Long
Abstract
Abstract Accurate discrimination of amyloid‐β (Aβ) peptides containing familial point mutations would advance the knowledge of their roles in early‐onset Alzheimer's disease. Herein, we simultaneously identified the mutant A21G, E22G, E22Q, and the wild‐type (WT) Aβ 18–26 peptides with aerolysin nanopore using a 3D blockage mapping strategy. The standard deviation of current blockade fluctuations ( σ b ) was proposed as a new supplement to current blockage ( I b / I 0 ) and duration time ( t D ) to profile the blockage characteristics of single molecules. Although the WT and A21G Aβ 18‐26 are indistinguishable in a traditional I b / I 0 ‐ t D 2D description, ∼87 % of the blockade events can be accurately classified with half reduction of false identification using a combination of I b / I 0 , t D, and σ b . This work offers an easy and reliable strategy to promote nanopore sensitivity of peptide mutants, leading to a more precise analysis of pathogenic mutations for developing effective diagnosis and treatment.