title: Influence of Aromatic Residues on the Material Characteristics of Aβ Amyloid Protofibrils at the Atomic Scale.
abstract: Amyloid fibrils, which cause a number of degenerative diseases, are insoluble under physiological conditions and are supported by native contacts. Recently, the effects of the aromatic residues on the Aβ amyloid protofibril were investigated in a ThT fluorescence study. However, the relationship between the material characteristics of the Aβ protofibril and its aromatic residues has not yet been investigated on the atomic scale. Here, we successfully constructed wild-type (WT) and mutated types of Aβ protofibrils by using molecular dynamics simulations. Through principle component analysis, we established the structural stability and vibrational characteristics of F20L Aβ protofibrils and compared them with WT and other mutated models such as F19L and F19LF20L. In addition, structural stability was assessed by calculating the elastic modulus, which showed that the F20L model has higher values than the other models studied. From our results, it is shown that aromatic residues influence the structural and material characteristics of Aβ protofibrils.
authors.affiliation: Department of Mechanical Engineering, Korea University, Seoul 136-701 (Republic of Korea).
authors.forename: Hyun Joon
authors.initials: HJ
authors.lastname: Chang
authors.affiliation: Department of Mechanical Engineering, Korea University, Seoul 136-701 (Republic of Korea).
authors.forename: Inchul
authors.initials: I
authors.lastname: Baek
authors.affiliation: Department of Mechanical Engineering, Korea University, Seoul 136-701 (Republic of Korea).
authors.forename: Myeongsang
authors.initials: M
authors.lastname: Lee
authors.affiliation: Department of Mechanical Engineering, Korea University, Seoul 136-701 (Republic of Korea). nass@korea.ac.kr.
authors.forename: Sungsoo
authors.initials: S
authors.lastname: Na
mesh_terms: D016229:Amyloid beta-Peptides / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D055119:Elastic Modulus; D056004:Molecular Dynamics Simulation; D016296:Mutagenesis; D010649:Phenylalanine / Q000737:chemistry; D025341:Principal Component Analysis; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary
chemical_list: D016229:Amyloid beta-Peptides; D010649:Phenylalanine
keywords: amyloid beta-peptides; mechanical properties; molecular dynamics; molecular modeling; stacking interactions