Peptoid Residues Make Diverse, Hyperstable Collagen Triple-Helices

Autor: Christopher P. Hill, Frank G. Whitby, Helen Kang, Julian L. Kessler, Zhao Qin, Yang Li, S. Michael Yu, Thomas E. Cheatham, Grace Kang
Rok vydání: 2021
Předmět:
Zdroj: J Am Chem Soc
ISSN: 1520-5126
0002-7863
DOI: 10.1021/jacs.1c00708
Popis: As the only ribosomally encoded N-substituted amino acid, proline promotes distinct secondary protein structures. The high proline content in collagen, the most abundant protein in the human body, is crucial to forming its hallmark structure: the triple-helix. For over five decades, proline has been considered compulsory for synthetic designs aimed at recapitulating collagen's structure and properties. Here we describe that N-substituted glycines (N-glys), also known as peptoid residues, exhibit a general triple-helical propensity similar to or greater than proline, enabling synthesis of stable triple-helical collagen mimetic peptides (CMPs) with unprecedented side chain diversity. Supported by atomic-resolution crystal structures as well as circular dichroism and computational characterizations spanning over 30 N-gly-containing CMPs, we discovered that N-glys stabilize the triple-helix primarily by sterically preorganizing individual chains into the polyproline-II helix. We demonstrated that N-glys with exotic side chains including a "click"-able alkyne and a photosensitive side chain enable CMPs for functional applications including the spatiotemporal control of cell adhesion and migration. The structural principles uncovered in this study open up opportunities for a new generation of collagen-mimetic therapeutics and materials.
Databáze: OpenAIRE