Abstract
All spiders produce protein-based biopolymer fibres that we call silk. The most studied of these silks is spider dragline silk, which is very tough and relatively abundant compared with other types of spider silks. Considerable research has been devoted to understanding the relationship between the molecular structure and mechanical properties of spider dragline silks. In this Review, we overview experimental and computational studies that have provided a wealth of detail at the molecular level on the highly conserved repetitive core and terminal regions of spider dragline silk. We also discuss the role of the nanocrystalline β-sheets and amorphous regions in determining the properties of spider silk fibres, endowing them with strength and elasticity. Additionally, we outline imaging techniques and modelling studies that elucidate the importance of the hierarchical structure of silk fibres at the molecular level. These insights into structure–function relationships can guide the reverse engineering of spider silk to enable the production of superior synthetic fibres.
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Acknowledgements
J.L.Y. acknowledges support from the US National Science Foundation (NSF DMR 1264801) and US Department of Defence Air Force Office of Scientific Research (FA9550-17-1-0282). A.v.d.V. acknowledges support from the US National Science Foundation (NSF CHE-1531590).
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The manuscript was researched and written with contributions from all three authors. J.L.Y. wrote the introduction and is responsible for much of the experimental sections of the review. A.v.d.V. researched and wrote the computational section of the review. B.R.C. researched and wrote the section on mechanical testing and several parts of the experimental sections.
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Yarger, J., Cherry, B. & van der Vaart, A. Uncovering the structure–function relationship in spider silk. Nat Rev Mater 3, 18008 (2018). https://doi.org/10.1038/natrevmats.2018.8
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DOI: https://doi.org/10.1038/natrevmats.2018.8
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