Protein Cages pp 139-188 | Cite as

Computational Mechanics of Viral Capsids

  • Melissa M. Gibbons
  • Luigi E. Perotti
  • William S. KlugEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1252)


Viral capsids undergo significant mechanical deformations during their assembly, maturation, and infective life-span. In order to characterize the mechanics of viral capsids, their response to applied external forces is analyzed in several experimental studies using, for instance, Atomic Force Microscope (AFM) indentation experiments. In recent years, a broader approach to study the mechanics of viral capsids has leveraged the theoretical tools proper of continuum mechanics. Even though the theory of continuum elasticity is most commonly used to study deformable bodies at larger macroscopic length scales, it has been shown that this very rich theoretical field can still offer useful insights into the mechanics of viral structures at the nanometer scale. Here we show the construction of viral capsid continuum mechanics models starting from different forms of experimental data. We will discuss the kinematics assumptions, the issue of the reference configuration, the material constitutive laws, and the numerical discretization necessary to construct a complete Finite Element capsid mechanical model. Some examples in the second part of the chapter will show the predictive capabilities of the constructed models and underline useful practical aspects related to efficiency and accuracy. We conclude each example by collecting several key findings discovered by simulating AFM indentation experiments using the constructed numerical models.

Key words

Viral capsids Continuum models Finite elements AFM indentation 


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Melissa M. Gibbons
    • 1
  • Luigi E. Perotti
    • 1
  • William S. Klug
    • 1
    Email author
  1. 1.Department of Mechanical and Aerospace EngineeringLos AngelesUSA

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