Program

P.31 -- Poster, IWTCP-3

Date: Wednesday, 29 July 2015

Time: 08h30 - 10h00

Study of amyloid fibrillation in a simple model

Nguyen Ba Hung (1,2), Trinh Xuan Hoang (1) and Hung T. Diep (3)

(1) Institute of Physics, Vietnam Academy of Science and Technology, Hanoi, Vietnam; (2) Vietnam Military Medical University, Hanoi, Vietnam; (3) University of Cergy-Pontoise, Cergy-Pontoise Cedex, France

In amyloids, polypeptides self-assemble into hierarchically organized fibrils. A fibril often consists of 2-6 filaments made up from $\beta$-sheets running parallel to each other. We study the fibrillation process using an XY spin model, in which the spins can rotate freely in the $xy$ plane, whereas elongation of filaments proceeds only in $z$ direction. To model the packing of filaments, each lattice site is allowed accommodate several spins belonging to different sublattices of the same spatial coordination. At intermediate temperatures, it is shown that fibrillation happens only when the total concentration of peptides exceeds some threshold value. When the latter is satisfied, the concentration of free peptides decreases as the total concentration of peptides increases.

Presenter: Nguyen Ba Hung