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Engineered elastomeric proteins with dual elasticity can be controlled by a molecular regulator

Nature Nanotechnology volume 3, pages 512516 (2008) | Download Citation

Abstract

Elastomeric proteins are molecular springs that confer excellent mechanical properties1,2,3,4,5 to many biological tissues and biomaterials. Depending on the role performed by the tissue or biomaterial, elastomeric proteins can behave as molecular springs1,2,6,7 or shock absorbers3,4,5,8,9,10. Here we combine single-molecule atomic force microscopy and protein engineering techniques to create elastomeric proteins that can switch between two distinct types of mechanical behaviour in response to the binding of a molecular regulator. The proteins are mechanically labile by design and behave as entropic springs with an elasticity that is governed by their configurational entropy. However, when a molecular regulator binds to the protein, it switches into a mechanically stable state and can act as a shock absorber. These engineered proteins effectively mimic and combine the two extreme forms of elastic behaviour found in natural elastomeric proteins, and thus represent a new type of smart nanomaterial that will find potential applications in nanomechanics and material sciences.

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Acknowledgements

This work was supported by the Natural Sciences and Engineering Research Council of Canada, Canada Research Chairs program and Canada Foundation for Innovation. H.L. is a Michael Smith Foundation for Health Research Career Investigator.

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Affiliations

  1. Department of Chemistry, The University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada

    • Yi Cao
    •  & Hongbin Li

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Contributions

Y.C. and H.L. conceived and designed the experiments. Y.C. performed the experiments and analysed the data. Y.C. and H.L. wrote the paper.

Corresponding author

Correspondence to Hongbin Li.

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DOI

https://doi.org/10.1038/nnano.2008.168

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