Microbially Synthesized Polymeric Amyloid Fiber Promotes β-Nanocrystal Formation and Displays Gigapascal Tensile Strength
- 12 July 2021
- journal article
- research article
- Published by American Chemical Society (ACS) in ACS Nano
- Vol. 15 (7), 11843-11853
- https://doi.org/10.1021/acsnano.1c02944
Abstract
The ability of amyloid proteins to form stable β-sheet nanofibrils has made them potential candidates for material innovation in nanotechnology. However, such a nanoscale feature has rarely translated into attractive macroscopic properties for mechanically demanding applications. Here, we present a strategy by fusing amyloid peptides with flexible linkers from spidroin; the resulting polymeric amyloid proteins can be biosynthesized using engineered microbes and wet-spun into macroscopic fibers. Using this strategy, fibers from three different amyloid groups were fabricated. Structural analyses unveil the presence of β-nanocrystals that resemble the cross-β structure of amyloid nanofibrils. These polymeric amyloid fibers have displayed strong and molecular-weight-dependent mechanical properties. Fibers made of a protein polymer containing 128 repeats of the FGAILSS sequence displayed an average ultimate tensile strength of 0.98 ± 0.08 GPa and an average toughness of 161 ± 26 MJ/m3, surpassing most recombinant protein fibers and even some natural spider silk fibers. The design strategy and the biosynthetic approach can be expanded to create numerous functional materials, and the macroscopic amyloid fibers will enable a wide range of mechanically demanding applications.Keywords
Funding Information
- Office of Naval Research (N000141912126)
- U.S. Department of Energy (DE-AC02-06CH11357)
- U.S. Department of Agriculture (20196702129943)
This publication has 80 references indexed in Scilit:
- Atomic View of a Toxic Amyloid Small OligomerScience, 2012
- Molecular basis for amyloid-β polymorphismProceedings of the National Academy of Sciences of the United States of America, 2011
- New Opportunities for an Ancient MaterialScience, 2010
- Native-sized recombinant spider silk protein produced in metabolically engineered Escherichia coli results in a strong fiberProceedings of the National Academy of Sciences of the United States of America, 2010
- Nanostructure and molecular mechanics of spider dragline silk protein assembliesJournal of The Royal Society Interface, 2010
- A protocol for the production of recombinant spider silk-like proteins for artificial fiber spinningNature Protocols, 2009
- Amyloid as a Depot for the Formulation of Long-Acting DrugsPLoS Biology, 2008
- Atomic structures of amyloid cross-β spines reveal varied steric zippersNature, 2007
- Protein Secondary Structure and Orientation in Silk as Revealed by Raman SpectromicroscopyBiophysical Journal, 2007
- Structure of the cross-β spine of amyloid-like fibrilsNature, 2005