7LQG

Cryo-EM of the KFE8 thinner nanotube (class 1, C2)

This is a non-PDB format compatible entry.

Summary for 7LQG

• Entry DOI: 10.2210/pdb7lqg/pdb
• EMDB information: 23483 23484 23485 23486 23487
• Descriptor: KFE8 peptide (1 entity in total)
• Functional Keywords: filament, self-assembly peptide filament, cryo-em, peptide fibril, nanotube, protein fibril
• Biological source: synthetic construct
• Total number of polymer chains: 144
• Total formula weight: 167666.40

Authors

Wang, F.,Gnewou, O.M.,Egelman, E.H.,Conticello, V.P. (deposition date: 2021-02-13, release date: 2021-06-30, Last modification date: 2023-11-15)

Primary citation

Wang, F.,Gnewou, O.,Wang, S.,Osinski, T.,Zuo, X.,Egelman, E.H.,Conticello, V.P.
Deterministic chaos in the self-assembly of beta sheet nanotubes from an amphipathic oligopeptide.
Matter, 4:3217-3231, 2021

PubMed Abstract: The self-assembly of designed peptides into filaments and other higher-order structures has been the focus of intense interest because of the potential for creating new biomaterials and biomedical devices. These peptide assemblies have also been used as models for understanding biological processes, such as the pathological formation of amyloid. We investigate the assembly of an octapeptide sequence, Ac-FKFEFKFE-NH, motivated by prior studies that demonstrated that this amphipathic β strand peptide self-assembled into fibrils and biocompatible hydrogels. Using high-resolution cryoelectron microscopy (cryo-EM), we are able to determine the atomic structure for two different coexisting forms of the fibrils, containing four and five β sandwich protofilaments, respectively. Surprisingly, the inner walls in both forms are parallel β sheets, while the outer walls are antiparallel β sheets. Our results demonstrate the chaotic nature of peptide self-assembly and illustrate the importance of cryo-EM structural analysis to understand the complex phase behavior of these materials at near-atomic resolution.

PubMed: 34632372
DOI: 10.1016/j.matt.2021.06.037

Experimental method

ELECTRON MICROSCOPY (3.4 Å)