Kinetics and mechanical stability of the fibril state control fibril formation time of polypeptide chains: A computational study

Journal Of Chemical Physics, 148, 2018

Authors: Kouza Maksim, Nguyen Truong Co, Li Mai Suan, Kmiecik Sebastian, Kolinski Andrzej, Kloczkowski Andrzej, Buhimschi Irina Alexandra

Abstract

Fibril formation resulting from protein misfolding and aggregation is a hallmark of several neurodegenerative diseases such as Alzheimer's and Parkinson's diseases. Despite much progress in the understanding of the protein aggregation process, the factors governing fibril formation rates and fibril stability have not been fully understood. Using lattice models, we have shown that the fibril formation time is controlled by the kinetic stability of the fibril state but not by its energy. Having performed all-atom explicit solvent molecular dynamics simulations with the GROMOS43a1 force field for fulll-ength amyloid beta peptides A beta(40) and A beta(42) and truncated peptides, we demonstrated that kinetic stability can be accessed via mechanical stability in such a way that the higher the mechanical stability or the kinetic stability, the faster the fibril formation. This result opens up a new way for predicting fibril formation rates based on mechanical stability that may be easily estimated by steered molecular dynamics. Published by AIP Publishing.