Altering Peptide Fibrillization by Polymer Conjugation

A strategy is presented that exploits the ability of synthetic polymers of different nature to disturb the strong self-assembly capabilities of amyloid based beta-sheet forming peptides. Following a convergent approach, the peptides of interest were synthesized via solid-phase peptide synthesis (SPPS) and the polymers via reversible addition-fragmentation chain transfer (RAFT') polymerization, followed by a copper(I) catalyzed azide-alkyne cycloaddition (CuAAC) to generate the desired peptide-polymer conjugates. This study focuses on a modified version of the core sequence of the beta-amyloid peptide (A beta), A beta(16-20) (KLVFF). The influence of attaching short poly(N-isopropylacrylamide) and poly(hydroxyethylacrylate) to the peptide sequences on the self-assembly properties of the hybrid materials were studied via infrared spectroscopy, TEM, circular dichroism and SAXS. The findings indicate that attaching these polymers disturbs the strong self-assembly properties of the biomolecules to a certain degree and permits to influence the aggregation of the peptides based on their beta-sheets forming abilities. This study presents an innovative route toward targeted and controlled assembly of amyloid-like fibers to drive the formation of polymeric nanomaterials.