Abstract
The capsids of icosahedral viruses are closed shells assembled from a hexagonal lattice of proteins with fivefold angular defects located at the icosahedral vertices. Elasticity theory predicts that these disclinations are subject to an internal compressive prestress, which provides an explanation for the link between size and shape of capsids. Using a combination of experiment and elasticity theory we investigate the question of whether macromolecular assemblies are subject to residual prestress, due to basic geometric incompatibility of the subunits. Here we report the first direct experimental test of the theory: by controlled removal of protein pentamers from the icosahedral vertices, we measure the mechanical response of so-called “whiffle ball” capsids of herpes simplex virus, and demonstrate the signature of internal prestress locked into wild-type capsids during assembly.
- Received 18 October 2011
DOI:https://doi.org/10.1103/PhysRevLett.109.168104
© 2012 American Physical Society
Synopsis
Protein Shells Take a Strength Test
Published 19 October 2012
The protein shells surrounding large viruses have built-in tension that determines their shapes.
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