Authors: S. Elhadj, G.H. Gilmer, R.W. Friddle, M. Estrada, M.E. Manchester, J.E. Johnson, J.J. De Yoreo, A. Noy
Affilation: Lawrence Livermore National Laboratory, United States
Pages: 499 - 500
Keywords: virus, Monte Carlo, template, force, binding energy, AFM
The use of macromolecular scaffolds for hierarchical organization of molecules and materials is a common strategy in living systems that leads to emergent behavior. One characteristic of this strategy is that it generates micron-scale structures from nm-scale building blocks possessing high-density functionality defined at Å-scales by active sites, typically on proteins complexes such as viral capsids. Here we describe an effort to relate interaction force measurements between viruses and modified substrates to the energy landscape during virus assembly on surfaces. Potentials and binding energies are then used in kinetic Monte Carlo simulations to predict assembly morphology under controlled conditions replicated experimentally. This model also provides a means to explore the nature of the governing interactions and to investigate the role of solvent interactions on inter-viral potentials. We use atomic force microscope (AFM) tips functionalized with specific chemical species to measure interactions in the assembly system, which includes Cow Pea Mosaic Virus (CPMV). CPMV virus particles were engineered to express specific functional groups to modulate the strength and kinetics of interactions and assembly morphology. We show that the CPMV morphological evolution predicted by the simulations correlates with AFM observations when the appropriate differences in adsorption energy between template and resist are used.