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Updated: Apr 20, 2026
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Generation and Assembly of Virus-Specific Nucleocapsids of the Respiratory Syncytial Virus
Published on: July 27, 2021
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Structural Polymorphs of Self-Assembled Brome Mosaic Virus Capsid Protein
N Harpell1, A L Duran-Meza1, H Elmer1
1Department of Chemistry and Biochemistry, University of California, Los Angeles, 607 Charles E. Young Drive East, Los Angeles, California 90095, United States.
The Journal of Physical Chemistry. B
|April 18, 2026
Summary
Brome Mosaic Virus capsid proteins self-assemble into various structures like spheres, rods, and sheets. These viral protein polymorphs are reversible and independent of their formation conditions.
Area of Science:
- Virology
- Structural Biology
- Biochemistry
Background:
- Brome Mosaic Virus (BMV), Cowpea Chlorotic Mottle Virus (CCMV), and Tobacco Mosaic Virus (TMV) can be reconstituted from purified RNA and capsid protein (CP).
- CCMV and TMV capsid proteins have been extensively studied for self-assembly polymorphs across various pH and ionic strengths.
- Understanding viral self-assembly is crucial for developing novel biotechnological applications.
Purpose of the Study:
- To map the polymorph distribution of Brome Mosaic Virus (BMV) capsid protein self-assemblies.
- To elucidate the types of quaternary structures formed by BMV capsid proteins.
- To investigate the influence of pH/ionic strength history on BMV polymorph formation and reversibility.
Main Methods:
- Utilized electron microscopy to visualize self-assembled structures.
- Employed atomic force microscopy (AFM) to analyze quaternary structures.
- Systematically varied pH and ionic strength conditions to study polymorph distribution.
Main Results:
- Identified spherical, rodlike, and sheet-like polymorphs of BMV capsid protein assemblies.
- Demonstrated that polymorph formation is independent of pH/ionic strength path history.
- Showcased the reversible interconversion between different self-assembled polymorphs.
Conclusions:
- BMV capsid proteins exhibit diverse self-assembly capabilities, forming distinct quaternary structures.
- The self-assembly process is robust, unaffected by the history of environmental conditions.
- Reversibility of polymorphs offers potential for controlled nanomaterial design and viral vector development.
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