Assembled viral-like nanoparticles from elastic capsomers and polyion

Area of Science:

• Biophysics
• Computational Chemistry
• Materials Science

Background:

• Viral capsids are protein shells protecting genetic material.
• Understanding self-assembly is crucial for designing synthetic nanoparticles.
• Polyion-driven assembly offers a route to complex macromolecular structures.

Purpose of the Study:

• To investigate the co-assembly of elastic capsomers driven by a polyion.
• To explore the kinetics and structural properties of resulting viral-like aggregates.
• To identify conditions favoring high yields of correctly formed nanoparticles.

Main Methods:

• Coarse-grained molecular dynamics simulations.
• Modeling of cationic capsomers and anionic polyions as beads connected by springs.
• Inclusion of counterions for charge neutralization.

Main Results:

• Identified conditions for high yield of viral-like nanoparticles.
• Demonstrated polyion overcharging within the capsid due to specific interactions and equilibria.
• Observed that capsomer elasticity improves capsid formation reliability.
• Discovered mechanisms involving cluster growth, polyion tethers, and monomer ejection/rebinding for annealing kinetically trapped structures.

Conclusions:

• Elasticity of capsomers is key to reliable viral capsid formation.
• Polyion interactions and elasticity drive the formation of stable, viral-like nanoparticles.
• Simulation results provide insights into designing self-assembling nanostructures.