Heterotypic Interactions between the 40- and 42-Residue Isoforms of β-Amyloid Peptides on Lipid Bilayer Surfaces.

Co-aggregation involving different amyloidogenic sequences has been emphasized recently in the modified amyloid cascade hypothesis. Yet, molecular-level interactions between two predominant β-amyloid peptide sequences, Aβ and Aβ, in the fibrillation process in membrane-mimicked environments remain unclear. Here, we report biophysical evidence that demonstrates the molecular-level interactions between Aβ and Aβ at the membrane-associated conucleation stage using dynamic nuclear polarization-enhanced solid-state NMR spectroscopy.