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His6, His13, and His14 residues in A? 1-40 peptide significantly and specifically affect oligomeric equilibria.

ABSTRACT: Oligomers of A? peptide are implicated as the most probable causative agent in Alzheimer's disease. However, their structural properties remain elusive due to the dynamic and heterogeneous character of oligomeric species coexisting in solution. Nevertheless, new approaches, mainly based on mass spectrometry, provide unique access to these different structural forms. Using these methods, we previously showed that the N-terminal, non-amyloidogenic region of A? is involved in the network of interactions specifically stabilizing oligomers. In the present study, we identified three histidine residues as active participants in this network. Detailed knowledge of the structural features that are potentially important for oligomer-mediated neurotoxicity is a prerequisite for the rational design of oligomerization modifiers.

SUBMITTER: Przygonska K

PROVIDER: S-EPMC6602940 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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His6, His13, and His14 residues in Aβ 1-40 peptide significantly and specifically affect oligomeric equilibria.

Przygońska Kaja K Pacewicz Magdalena M Sadowska Wiktoria W Poznański Jarosław J Bal Wojciech W Dadlez Michał M

Scientific reports 20190701 1

Oligomers of Aβ peptide are implicated as the most probable causative agent in Alzheimer's disease. However, their structural properties remain elusive due to the dynamic and heterogeneous character of oligomeric species coexisting in solution. Nevertheless, new approaches, mainly based on mass spectrometry, provide unique access to these different structural forms. Using these methods, we previously showed that the N-terminal, non-amyloidogenic region of Aβ is involved in the network of interac ...[more]

PMID: 31263161

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