%0 Journal Article
%A Smorodina, Eva
%A Kav, Batuhan
%A Fatafta, Hebah
%A Strodel, Birgit
%T Effects of ion type and concentration on the structure and aggregation of the amyloid peptide A β16−22$$ {\boldsymbol{\beta}}_{16-22} $$
%J Proteins
%V 93
%N 8
%@ 0887-3585
%C New York, NY
%I Wiley-Liss
%M FZJ-2023-05505
%P 1369-1382
%D 2025
%X Among the various factors controlling the amyloid aggregation process, the influences ofions on the aggregation rate and the resultingstructures are important aspects to con-sider, which can be studied by molecular simulations. There is a wide variety of proteinforce fields and ion models, raising the question of which model to use in such studies. Toaddress this question, we perform molecular dynamics simulations of Aβ16–22, a fragmentof the Alzheimer's amyloidβpeptide, using different protein force fields, AMBER99SB-disp (A99-d) and CHARMM36m (C36m), and different ion parameters. The influences ofNaCl and CaCl2at various concentrations are studied and compared with the systemswithout the addition of ions. Our results indicate a sensitivity of the peptide-ion interac-tions to the different ion models. In particular, we observe a strong binding of Ca2+to res-idue E22 with C36m and also with the Åqvist ion model used together with A99-d, whichslightly affects the monomeric Aβ16–22structures and the aggregation rate, but signifi-cantly affects the oligomer structures formedin the aggregation simulations. For example,at high Ca2+concentrations, there was a switch from an antiparallel to a parallelβ-sheet.Such ionic influences are of biological relevance because local ion concentrations canchange in vivo and could help explain thepolymorphism of amyloid fibrils.
%F PUB:(DE-HGF)16
%9 Journal Article
%$ 37964477
%U <Go to ISI:>//WOS:001105186900001
%R 10.1002/prot.26635
%U https://juser.fz-juelich.de/record/1019568