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Updated: Jun 24, 2026
09:47
Simple and Robust in vivo and in vitro Approach for Studying Virus Assembly
Published on: March 1, 2012
Virus maturation involving large subunit rotations and local refolding
J F Conway1, W R Wikoff, N Cheng
1Laboratory of Structural Biology Research, National Institute of Arthritis, Musculoskeletal and Skin Diseases, Bethesda, MD 20892, USA.
Science (New York, N.Y.)
|April 28, 2001
Summary
Bacteriophage HK97 capsid undergoes major structural changes from precursor to infectious form. These transformations involve rotations and refolding, stabilizing the capsid and preparing it for DNA packaging.
Area of Science:
- Structural biology
- Virology
- Biophysics
Background:
- Viral capsids undergo significant conformational changes to become infectious.
- The structure of bacteriophage HK97 Head-II has been determined, showing a cross-linked topology.
Purpose of the Study:
- To visualize the precursor of bacteriophage HK97 capsid, Prohead-II.
- To model the conformational changes from Prohead-II to Head-II.
Main Methods:
- Cryoelectron microscopy was used to visualize Prohead-II.
- Crystallographic data of Head-II was adapted to model the conformational change.
Main Results:
- Rigid-body rotations of approximately 40 degrees were observed.
- Two protein motifs refolded during the conformational change.
- Capsid stabilization increased due to greater buried surface area at interfaces.
- Cross-link-forming residues were brought closer together.
Conclusions:
- The conformational changes stabilize the bacteriophage capsid.
- The negatively charged inner surface of Prohead-II suggests DNA packaging triggers the transition electrostatically.
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