Peptidic Scaffolds To Reduce the Interaction of Cu(II) Ions with β-Amyloid Protein.

Competitive Cu(II)-binding studies have been carried out between five decapeptides (both acyclic and cyclic), namely , , , and , and the Aβ(1-16) and Aβ(1-40) fragments. Conformational constraints in such peptidic scaffolds affect their copper-binding affinity, which can be tuned. In the present study, the ability of these peptides to compete with Aβ has been assessed , with the objective to examine whether such soft chelating agents may be used to lessen the deleterious interaction of Cu(II) with Aβ.

The role of methylation in the copper(ii) coordination properties of a His-containing decapeptide.

N-Methylation of the peptide amide bond has proven to be a powerful strategy to fine-tune the conformation and properties of peptides. In this context and for the first time, we show that N-methylation can also be used to control the copper(ii) coordination properties of peptides and stabilize at high pH values the copper(ii) species lacking amidate coordination. Namely, we have prepared a derivative of the O-Asp peptide where the copper(ii) coordinating amino acids, i.