Metal Binding to Aβ Peptides Inhibits Interaction with Cytochrome : Insights from Abiological Constructs.

Aβ(1-40) peptide is mutated to introduce cysteine residue to allow formation of organized self-assembled monolayers (SAMs) on Au electrodes. Three mutants of this peptide are produced, which vary in the position of the inserted cysteine residue. Fourier transform infrared data on these peptide SAMs show the presence of both α helices and β sheet in these Aβ constructs. These peptide constructs interact with cytochrome (Cyt), allowing electron transfer between Cyt and the electrode via the Aβ peptides. Binding of metals like Zn or Cu induces changes in the morphologies of these assemblies, making them fold, which inhibits their spontaneous interaction with Cyt.