Self-assembly Process and Oligomeric State of peptide-polymer conjugates at the Air-Water Interface

Coiled-coil peptide-polymer conjugates are an emerging class of biomaterials. Fundamental understanding of the coiled-coil oligomeric state and assembly process of these hybrid building blocks is necessary to exert control over their assembly into well-defined structures. Here, we studied the effect of peptide structure and PEGylation on the self-assembly process and oligomeric state of a Langmuir monolayer of amphiphilic coiled-coil peptide-polymer conjugates using x-ray reflectivity (XR) and grazing-incidence x-ray diffraction (GIXD). Our results show that the oligomeric state of PEGylated amphiphiles based on 3-helix bundle-forming peptide is surface pressure dependent, a mixture of dimers and trimers was formed at intermediate surface pressure but transitions into trimers completely upon increasing surface pressure. Moreover, the inter-helical distance within the coiled-coil bundle of 3-helix peptide-PEG conjugate amphiphiles was not perturbed under high surface pressure. Present studies provide valuable insights into the self-assembly process of hybrid peptide-polymer conjugates and guidance to develop biomaterials with controlled multivalency of ligand presentation.


Reidar Lund1,2, JooChuan Ang1, Jessica Y. Shu1, Ting Xu1,2,3

1Department of Materials Science and Engineering, University of California, Berkeley 94720, USA

2Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley 94720, USA

3Department of Chemistry, University of California, Berkeley 94720, USA

Biomacromolecules, 2016, 17, pp 3964-3972

DOI: 10.1021/acs.biomac.6b01356