AVS 66th International Symposium & Exhibition
    Biomaterial Interfaces Division Monday Sessions
       Session BI+AS-MoA

Paper BI+AS-MoA3
Antimicrobial Cyclic Peptide Polymer Nanopores

Monday, October 21, 2019, 2:20 pm, Room A120-121

Session: Cutting Edge Bio: Bio-Nano, Bio-Energy, 3D Bio
Presenter: Kenan Fears, US Naval Research Laboratory
Authors: K.P. Fears, US Naval Research Laboratory
L. Estrella, US Naval Research Laboratory
Correspondent: Click to Email
We present a new class of bioinspired nanomaterials that are stabilized by a combination of covalent and hydrogen bonds. Prior work by others has shown that cyclic peptides can self-assemble to form supramolecular assemblies through backbone-backbone hydrogen bonding. To improve upon this molecular architecture, we develop a synthesis route to polymerize cyclic peptides and form a linear polymer chain that can transition between a rigid nanorod and a “soft” unfolded conformation. For a cyclic peptide polymer containing amine-terminated side chains on each ring, we demonstrate self-assembly can be triggered in aqueous solutions by varying the pH. We measure the elastic modulus of the rigid nanorods to be ca. 50 GPa, which is comparable to our molecular dynamics (MD) prediction (ca. 64 GPa). Our results highlight the uniqueness of our molecular architecture, namely their exemplary toughness (up to 3 GJ m-3), in comparison to other cyclic peptide-based assemblies. Finally, we demonstrate the amphiphilic cyclic peptide nanopores are capable of inserting into the membrane of both gram-negative and gram-positive bacteria, and causing their deaths by disrupting their osmotic pressure.