BIOINSPIRED PEPTIDE NANOWIRES` SEQUENCE AND STRUCTURE EFFECTS ON PROTON TRANSPORT

The ability to de-novo design peptides (short proteins segments) to self-assemble into functional structures has attracted an extensive attention in recent years, especially towards their implementation in biomedical and biotechnological applications. Many of the self-assembling peptide sequences include charged amino acids, making the resulting nanostructures amenable to proton conduction. Motivated by the opportunity to employ this phenomenon in novel bioelectronic applications, the aim of the work I will present was to discover the structural factors that govern proton transport processes in these biomimetic structures. I will demonstrate that proton transport is enhanced significantly by the introduction of a single charged amino acid into the sequence of a heptapeptide that self-assembled into fibrils.¹ Moreover, I will show that acidic residues are more effective than basic ones in promoting proton-conduction of the peptide fibrils due to two orders of magnitude larger doping effect, and a threefold higher charge carrier mobility value. I will further demonstrate that the structural motif of the monomeric peptides has a critical impact on proton conductivity of their assemblies, as well. I will show that D,L a-cyclic peptide assemblies exhibit superior conductivity and better thermal stability than assemblies of linear peptides with a similar sequence.

1. Silberbush, O., Amit, M., Roy, S., Ashkenasy, N., Adv. Funct. Mater. 2017, 27 (8).