Charged surfactants induce a non-fibrillar aggregation pathway of amyloid-beta peptide.
The amyloid β-peptide with a sequence of 42 amino acids is the major constituent of extracellular amyloid deposits in Alzheimer's disease plaques. The control of the peptide self-assembly is difficult to achieve because the process is fast and is affected by many variables. In this paper, we describe the effect of different charged and non-charged surfactants on Aβ(₁₋₄₂) fibrillation to define common alternate aggregation pathways. The characterization of the peptide-surfactant interactions by ultra-structural analysis, thioflavin T assay and secondary structure analysis, suggested that charged surfactants interact with Aβ(₁₋₄₂) through electrostatic interactions. Charged micelles slow down the aggregation process and stabilize the peptide in the oligomeric state, whereas non-charged surfactants promote the Aβ(₁₋₄₂) fibril formation.
LEPAE, Department of Chemical Engineering, Faculty of Engineering, University of Porto, Rua Roberto Frias, Porto, Portugal.
Joana A
JA
Loureiro
Sandra
S
Rocha
Maria do Carmo
Mdo C
Pereira
D000682:Amyloid / Q000737:chemistry* / Q000648:ultrastructure; D016229:Amyloid beta-Peptides / Q000737:chemistry* / Q000648:ultrastructure; D052160:Benzothiazoles; D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000737:chemistry; D005456:Fluorescent Dyes / Q000737:chemistry; D005583:Fourier Analysis; D005960:Glucosides / Q000737:chemistry; D006801:Humans; D007700:Kinetics; D008823:Micelles; D010446:Peptide Fragments / Q000737:chemistry* / Q000648:ultrastructure; D011485:Protein Binding; D055503:Protein Multimerization; D020836:Protein Structure, Quaternary; D017433:Protein Structure, Secondary; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D013501:Surface-Active Agents / Q000737:chemistry*; D013844:Thiazoles / Q000737:chemistry
D000682:Amyloid; D016229:Amyloid beta-Peptides; D052160:Benzothiazoles; D002593:Cetrimonium Compounds; D005456:Fluorescent Dyes; D005960:Glucosides; D008823:Micelles; D010446:Peptide Fragments; D013501:Surface-Active Agents; D013844:Thiazoles; C075222:amyloid beta-protein (1-42); C009462:thioflavin T; C018619:octyl-beta-D-glucoside; D012967:Sodium Dodecyl Sulfate; D000077286:Cetrimonium
Alzheimer; aggregation; beta amyloid; oligomers; surfactants