Mechanism of Side Chain-Controlled Proton Conductivity in Bioinspired Peptidic Nanostructures.

Journal Article (Journal Article)

Bioinspired peptide assemblies are promising candidates for use as proton-conducting materials in electrochemical devices and other advanced technologies. Progress toward applications requires establishing foundational structure-function relationships for transport in these materials. This experimental-theoretical study sheds light on how the molecular structure and proton conduction are linked in three synthetic cyclic peptide nanotube assemblies that comprise the three canonical basic amino acids (lysine, arginine, and histidine). Experiments find an order of magnitude higher proton conductivity for lysine-containing peptide assemblies compared to histidine and arginine containing assemblies. The simulations indicate that, upon peptide assembly, the basic amino acid side chains are close enough to enable direct proton transfer. The proton transfer kinetics is determined in the simulations to be governed by the structure and flexibility of the side chains. Together, experiments and theory indicate that the proton mobility is the main determinant of proton conductivity, critical for the performance of peptide-based devices.

Full Text

Duke Authors

Cited Authors

  • Roy, S; Zheng, L; Silberbush, O; Engel, M; Atsmon-Raz, Y; Miller, Y; Migliore, A; Beratan, DN; Ashkenasy, N

Published Date

  • November 2021

Published In

Volume / Issue

  • 125 / 46

Start / End Page

  • 12741 - 12752

PubMed ID

  • 34780197

Electronic International Standard Serial Number (EISSN)

  • 1520-5207

International Standard Serial Number (ISSN)

  • 1520-6106

Digital Object Identifier (DOI)

  • 10.1021/acs.jpcb.1c08857

Language

  • eng