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Updated: Jun 24, 2026
09:08
Generation and Assembly of Virus-Specific Nucleocapsids of the Respiratory Syncytial Virus
Published on: July 27, 2021
A theory for viral capsid assembly around electrostatic cores
1Department of Physics, Brandeis University, Waltham, Massachusetts 02454, USA. hagan@brandeis.edu
The Journal of Chemical Physics
|March 26, 2009
Summary
We developed theories for viral capsid assembly around charged nanoparticles. Our models predict efficient assembly above a charge density threshold, matching experimental observations but highlighting areas for further study.
Area of Science:
- Biophysics
- Materials Science
- Computational Biology
Background:
- Viral capsid proteins self-assemble into protective shells.
- Recent experiments show brome mosaic virus capsids assembling around functionalized nanoparticles.
- Understanding this assembly process is key for nanotechnology and virology.
Purpose of the Study:
- To develop theoretical models for viral capsid assembly on charged cores.
- To explain experimental observations of capsid assembly around nanoparticles.
- To identify discrepancies and suggest future research directions.
Main Methods:
- Developed equilibrium and kinetic theories for protein assembly.
- Modeled protein-surface interactions using the nonlinear Poisson-Boltzmann equation.
- Compared theoretical predictions with experimental light scatter data.
Main Results:
- Predicted a threshold charge density for efficient capsid assembly.
- Observed rapid light scatter increase without a lag phase, consistent with experiments.
- Identified discrepancies in charge density dependence and growth phase, suggesting metastable states.
Conclusions:
- Theoretical models provide insight into nanoparticle-directed viral capsid assembly.
- Discrepancies suggest the presence of complex intermediate states in experimental systems.
- Findings have implications for designing nanoparticle-based systems and understanding biological assembly processes.
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