Cryo-EM of Helical Polymers

• Type of Material: Article
• Authors: Fengbin Wang, University of Virginia; Ordy Gnewou, Emory University; Armin Solemanifar, Emory University; Vincent Conticello, Emory University; Edward H. Egelman, University of Virginia
• Language: English
• Date: 2022-02-08
• Publisher: American Chemical Society
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: © 2022 American Chemical Society
• Final Published Version (URL): https://doi.org/10.1021%2Facs.chemrev.1c00753
• Title of Journal or Parent Work: Chemical Review
• Grant/Funding Information: This work was supported by NIH R35GM122510 (to E.H.E.) and K99GM138756 (to F.W.), and NSF DMR-1534317 (to V.P.C.).
• Keywords: synthetic soft matter non-covalent polymers; cryo-EM; helical macromolecular assemblies
• Research Categories: Biology, Molecular

Abstract

While the application of cryo-EM to helical polymers in biology has a long history, due to the huge number of helical macromolecular assemblies in viruses, bacteria, archaea and eukaryotes, the use of cryo-EM to study synthetic soft matter non-covalent polymers has been much more limited. This has mainly been due to the lack of familiarity with cryo-EM in the materials science and chemistry communities, in contrast to the fact that cryo-EM was developed as a biological technique. Nevertheless, the relatively few structures of self-assembled peptide nanotubes and ribbons solved at near-atomic resolution by cryo-EM have demonstrated that cryo-EM should be the method of choice for structural analysis of synthetic helical filaments. In addition, cryo-EM has also demonstrated that the self-assembly of soft matter polymers has enormous potential for polymorphism, something that may be obscured by techniques such as scattering and spectroscopy. These cryo-EM structures have revealed how far we currently are from being able to predict the structure of these polymers due to their chaotic self-assembly behavior.