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Updated: Jul 3, 2026
09:08
Generation and Assembly of Virus-Specific Nucleocapsids of the Respiratory Syncytial Virus
Published on: July 27, 2021
The semipermeability of simple spherical virus capsids.
A C Durham1, J Witz, J B Bancroft
1Institut de Biologie Moleculaire et Cellulaire du C.N.R.S., 15 rue Descartes, 67084 Strasbourg Cedex, France.
Virology
|February 1, 1984
Summary
Virus protein capsids exhibit hysteresis loops during swelling and contraction, revealing semipermeable properties similar to lipid membranes. This suggests intermediate states in virion swelling and ion handling.
Area of Science:
- Biophysics
- Virology
- Materials Science
Background:
- Viruses possess protein capsids that interact with ions.
- Understanding these interactions is crucial for virology and drug delivery.
- Previous studies have not fully explored the ion-binding properties of viral capsids.
Purpose of the Study:
- To investigate the ion-binding properties of various plant virus capsids.
- To characterize the hysteresis loops observed during virion swelling and contraction.
- To propose a new theory for titration hysteresis in simple viruses.
Main Methods:
- Hydrogen-ion titration curves were generated for tomato bushy stunt virus, cowpea chlorotic mottle virus strains, and turnip crinkle virus.
- Eggplant mosaic virus was studied under varying conditions (salt concentration, urea, temperature).
Main Results:
- Archetypal hysteresis loop shapes were observed across several virus groups, indicating multiple intermediate states during swelling.
- Eggplant mosaic virus capsids showed limited ion permeability under mild conditions.
- Cation-binding sites on eggplant mosaic virus capsids were revealed under harsher conditions.
Conclusions:
- Viral protein capsids are inherently semipermeable, exhibiting ion-handling properties previously attributed to lipid membranes.
- Titration hysteresis in simple viruses is explained by the semipermeable nature of their protein capsids.
- This finding has implications for understanding virus assembly, stability, and potential therapeutic applications.
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