title: Investigation of the aggregation process of amyloid-β-(16-22) peptides and the dissolution of intermediate aggregates.
abstract: The aggregation processes of amyloid-β-(16-22) peptides (Aβ16-22) are investigated by atomic force microscopy (AFM). It is found that Aβ16-22 peptides quickly aggregate from monomers to oligomers and flakelike structures and finally to fibrils. In particular, unusual morphology change is observed in an early stage of aggregation; that is, the originally formed flakelike structures would disappear in the following aggregation processes. To determine the evolution of the flakelike structures, in situ AFM imaging is carried out in liquid to reveal the real-time morphology change of Aβ16-22. The results provide clear evidence that the flakelike structures are in an unstable intermediate state, which would be dissolved into oligomers or short protofibrils for reorganization. Further fluorescence and attenuated total reflectance Fourier transform infrared (ATR-FTIR) experiments on thioflavin T(ThT) suggest that those flakelike structures contain β-sheet components.
authors.affiliation: State Key Laboratory of Surface Physics, Fudan University , 220 Handan Road, Shanghai 200433, PR China.
authors.forename: Dongdong
authors.initials: D
authors.lastname: Lin
authors.forename: Yin
authors.initials: Y
authors.lastname: Luo
authors.forename: Shan
authors.initials: S
authors.lastname: Wu
authors.forename: Qianqian
authors.initials: Q
authors.lastname: Ma
authors.forename: Guanghong
authors.initials: G
authors.lastname: Wei
authors.forename: Xinju
authors.initials: X
authors.lastname: Yang
mesh_terms: D016229:Amyloid beta-Peptides / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D008958:Models, Molecular; D010446:Peptide Fragments / Q000737:chemistry*; D055503:Protein Multimerization; D017433:Protein Structure, Secondary
chemical_list: D016229:Amyloid beta-Peptides; D010446:Peptide Fragments; C417223:amyloid beta-protein (16-22)