Membrane interactions and the effect of metal ions of the amyloidogenic fragment Aβ(25-35) in comparison to Aβ(1-42)

Abstract

Aβ(1-42) peptide, found as aggregated species in Alzheimer's disease brain, is linked to the onset of Alzheimer's disease. Many reports have linked metals to inducing Aβ aggregation and amyloid plaque formation. Aβ(25-35), a fragment from the C-terminal end of Aβ(1-42), lacks the metal coordinating sites found in the full-length peptide and is neurotoxic to cortical cortex cell cultures. We report solid-state NMR studies of Aβ(25-35) in model lipid membrane systems of anionic phospholipids and cholesterol, and compare structural changes to those of Aβ(1-42). When added after vesicle formation, Aβ(25-35) was found to interact with the lipid headgroups and slightly perturb the lipid acyl-chain..