Fiber diffraction data indicate a hollow core for the Alzheimer's aβ 3-fold symmetric fibril.
Amyloid β protein (Aβ), the principal component of the extracellular plaques found in the brains of patients with Alzheimer's disease, forms fibrils well suited to structural study by X-ray fiber diffraction. Fiber diffraction patterns from the 40-residue form Aβ(1-40) confirm a number of features of a 3-fold symmetric Aβ model from solid-state NMR (ssNMR) but suggest that the fibrils have a hollow core not present in the original ssNMR models. Diffraction patterns calculated from a revised 3-fold hollow model with a more regular β-sheet structure are in much better agreement with the observed diffraction data than patterns calculated from the original ssNMR model. Refinement of a hollow-core model against ssNMR data led to a revised ssNMR model, similar to the fiber diffraction model.
Department of Biological Sciences, Vanderbilt University, Nashville, TN 37235-1634, USA.
Michele
M
McDonald
Hayden
H
Box
Wen
W
Bian
Amy
A
Kendall
Robert
R
Tycko
Gerald
G
Stubbs
D000544:Alzheimer Disease; D016229:Amyloid beta-Peptides / Q000737:chemistry*; D006801:Humans; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular; D010446:Peptide Fragments / Q000737:chemistry*; D058225:Plaque, Amyloid / Q000737:chemistry*; D011487:Protein Conformation; D014961:X-Ray Diffraction
D016229:Amyloid beta-Peptides; D010446:Peptide Fragments; C078592:amyloid beta-protein (1-40)