Physics – Biological Physics
Scientific paper
2006-08-16
Physics
Biological Physics
24 pages, 10 figures, submitted to Biophysical Journal
Scientific paper
Recent Atomic Force Microscope (AFM) nanoindentation experiments measuring mechanical response of the protein shells of viruses have provided a quantitative description of their strength and elasticity. To better understand and interpret these measurements, and to elucidate the underlying mechanisms, this paper adopts a course-grained modeling approach within the framework of three-dimensional nonlinear continuum elasticity. Homogeneous, isotropic, elastic, thick shell models are proposed for two capsids: the spherical Cowpea Chlorotic Mottle Virus (CCMV), and the ellipsocylindrical bacteriophage $\phi 29$. As analyzed by the finite element method, these models enable parametric characterization of the effects of AFM tip geometry, capsid dimensions, and capsid constitutive descriptions. The generally nonlinear force response of capsids to indentation is shown to be insensitive to constitutive details, and greatly influenced by geometry. Nonlinear stiffening and softening of the force response is dependent on the AFM tip dimensions and shell thickness. Fits of the models capture the roughly linear behavior observed in experimental measurements and result in estimates of Young's moduli of $\approx$280--360 MPa for CCMV and $\approx$4.5 GPa for $\phi 29$.
Gibbons Melissa M.
Klug William S.
No associations
LandOfFree
Nonlinear Finite Element Analysis of Nanoindentation of Viral Capsids does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Nonlinear Finite Element Analysis of Nanoindentation of Viral Capsids, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Nonlinear Finite Element Analysis of Nanoindentation of Viral Capsids will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-220329