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arXiv · 2011.06222

Hamiltonian Dynamics of Saturated Elongation in Amyloid Fiber Formation

Liu Hong·Xizhou Liu·Thomas C. T. Michaels·Tuomas P. J. Knowles
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Abstract

Elongation is a fundament process in amyloid fiber growth, which is normally characterized by a linear relationship between the fiber elongation rate and the monomer concentration. However, in high concentration regions, a sub-linear dependence was often observed, which could be explained by a universal saturation mechanism. In this paper, we modeled the saturated elongation process through a Michaelis-Menten like mechanism, which is constituted by two sub-steps -- unspecific association and dissociation of a monomer with the fibril end, and subsequent conformational change of the associated monomer to fit itself to the fibrillar structure. Typical saturation concentrations were found to be $7-70\mu M$ for A$\beta$40, $\alpha$-synuclein and etc. Furthermore, by using a novel Hamiltonian formulation, analytical solutions valid for both weak and strong saturated conditions were constructed and applied to the fibrillation kinetics of $\alpha$-synuclein and silk fibroin.

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Liu Hong, Xizhou Liu, Thomas C. T. Michaels, Tuomas P. J. Knowles. 2020-11-12. Hamiltonian Dynamics of Saturated Elongation in Amyloid Fiber Formation. https://arxiv.org/abs/2011.06222

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