Computational Analysis of the Effect of [Tea][Ms] and [Tea][H2PO4] Ionic Liquids on the Structure and Stability of Aβ(17-42) Amyloid Protofibrils

16 December 2020, Version 1
This content is a preprint and has not undergone peer review at the time of posting.

Abstract

Experimental studies have reported the possibility of affecting the growth/dissolution of amyloid fibres by the addition of organic salts of the room-temperature ionic-liquids family, raising the tantalizing prospect of controlling these processes at physiological conditions. The effect of [Tea][Ms] and [Tea][H2PO4] at various concentrations on the structure and stability of a simple model of Aβ42 fibrils has been investigated by computational means. Free energy computations show that both [Tea][Ms] and [Tea][H2PO4] decrease the stability of fibrils with respect to isolated peptides in solution, and the effect is significantly stronger for [Tea][Ms]. The secondary structure of fibrils is not much affected, but single peptides in solution show a marked decr
ease in their $\beta$-strand character, and an increase in
$\alpha$-propensity, again especially for [Tea][Ms]. These observations, consistent with the experimental picture, can be traced to two primary effects, i.e., the different ionicity of the [Tea][Ms] and [Tea][H2PO4] water solutions, and the remarkable affinity of peptides for [Ms]^- anions, due to a multiplicity of H-bonds.

Keywords

Amyloids
Room Temperature Ionic Liquids
Molecular Dynamics
Free Energy Computations

Supplementary materials

Title
Description
Actions
Title
SI
Description
Actions

Comments

Comments are not moderated before they are posted, but they can be removed by the site moderators if they are found to be in contravention of our Commenting Policy [opens in a new tab] - please read this policy before you post. Comments should be used for scholarly discussion of the content in question. You can find more information about how to use the commenting feature here [opens in a new tab] .
This site is protected by reCAPTCHA and the Google Privacy Policy [opens in a new tab] and Terms of Service [opens in a new tab] apply.