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arXiv · 0904.2505

Elongation dynamics of amyloid fibrils: a rugged energy landscape picture

Chiu Fan Lee·James Loken·Letitia Jean·David J. Vaux
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Abstract

Protein amyloid fibrils are a form of linear protein aggregates that are implicated in many neurodegenerative diseases. Here, we study the dynamics of amyloid fibril elongation by performing Langevin dynamic simulations on a coarse-grained model of peptides. Our simulation results suggest that the elongation process is dominated by a series of local minimum due to frustration in monomer-fibril interactions. This rugged energy landscape picture indicates that the amount of recycling of monomers at the fibrils' ends before being fibrilized is substantially reduced in comparison to the conventional two-step elongation model. This picture, along with other predictions discussed, can be tested with current experimental techniques.

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Chiu Fan Lee, James Loken, Letitia Jean, David J. Vaux. 2009-04-16. Elongation dynamics of amyloid fibrils: a rugged energy landscape picture. https://doi.org/10.1103/physreve.80.041906

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