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Quenched hydrogen-deuterium exchange NMR of a disease-relevant A?(1-42) amyloid polymorph.

ABSTRACT: Alzheimer's disease is associated with the aggregation into amyloid fibrils of A?(1-42) and A?(1-40) peptides. Interestingly, these fibrils often do not obtain one single structure but rather show different morphologies, so-called polymorphs. Here, we compare quenched hydrogen-deuterium (H/D) exchange of a disease-relevant A?(1-42) fibril for which the 3D structure has been determined by solid-state NMR with H/D exchange previously determined on another structural polymorph. This comparison reveals secondary structural differences between the two polymorphs suggesting that the two polymorphisms can be classified as segmental polymorphs.

SUBMITTER: Walti MA

PROVIDER: S-EPMC5358797 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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Quenched hydrogen-deuterium exchange NMR of a disease-relevant Aβ(1-42) amyloid polymorph.

Wälti Marielle Aulikki MA Orts Julien J Riek Roland R

PloS one 20170320 3

Alzheimer's disease is associated with the aggregation into amyloid fibrils of Aβ(1-42) and Aβ(1-40) peptides. Interestingly, these fibrils often do not obtain one single structure but rather show different morphologies, so-called polymorphs. Here, we compare quenched hydrogen-deuterium (H/D) exchange of a disease-relevant Aβ(1-42) fibril for which the 3D structure has been determined by solid-state NMR with H/D exchange previously determined on another structural polymorph. This comparison reve ...[more]

PMID: 28319116

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