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Updated: Jun 24, 2026

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.
Abstract:
Large-scale conformational changes transform viral precursors into infectious virions. The structure of bacteriophage HK97 capsid, Head-II, was recently solved by crystallography, revealing a catenated cross-linked topology. We have visualized its precursor, Prohead-II, by cryoelectron microscopy and modeled the conformational change by appropriately adapting Head-II. Rigid-body rotations ( approximately 40 degrees) cause switching to an entirely different set of interactions; in addition, two motifs undergo refolding. These changes stabilize the capsid by increasing the surface area buried at interfaces and bringing the cross-link-forming residues, initially approximately 40 angstroms apart, close together. The inner surface of Prohead-II is negatively charged, suggesting that the transition is triggered electrostatically by DNA packaging.
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