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Updated: Jul 18, 2026
09:47
Simple and Robust in vivo and in vitro Approach for Studying Virus Assembly
Published on: March 1, 2012
Distinguishing reversible from irreversible virus capsid assembly
1Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA. adam-zlotnick@ouhsc.edu
Journal of Molecular Biology
|December 13, 2006
Summary
Viral capsid assembly is often driven by many weak interactions. This study compares reversible and irreversible reactions, finding reversible processes are key to understanding viral assembly and avoiding kinetic traps.
Area of Science:
- Virology
- Biophysics
- Biochemistry
Background:
- Viral capsids assemble from numerous protein subunits.
- The precise mechanisms of viral assembly are not fully understood.
- Assembly reactions can be reversible or irreversible.
Purpose of the Study:
- To compare the assembly behaviors of reversible and irreversible reactions.
- To investigate the role of weak interactions in viral capsid formation.
- To understand how kinetic traps affect viral assembly.
Main Methods:
- Mass action calculations were used to model assembly.
- Kinetic simulations described assembly as a cascade of reactions.
- Predicted behaviors of reversible and irreversible reactions were compared.
Main Results:
- Reversible reactions exhibit a pseudo-critical concentration.
- Irreversible reactions consume all free subunits and are prone to kinetic traps.
- Even with an irreversible final step, overall assembly resembles reversible reactions.
Conclusions:
- Viral assembly likely involves numerous weak, reversible interactions.
- Understanding reaction reversibility is crucial for predicting viral assembly outcomes.
- Weak interactions may prevent the formation of kinetic traps during capsid formation.
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