Publication Date:
2001-04-28
Description:
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.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Conway, J F -- Wikoff, W R -- Cheng, N -- Duda, R L -- Hendrix, R W -- Johnson, J E -- Steven, A C -- AI40101/AI/NIAID NIH HHS/ -- R01 GM47795/GM/NIGMS NIH HHS/ -- New York, N.Y. -- Science. 2001 Apr 27;292(5517):744-8.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Laboratory of Structural Biology Research, National Institute of Arthritis, Musculoskeletal and Skin Diseases, Bethesda, MD 20892, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/11326105" target="_blank"〉PubMed〈/a〉
Keywords:
Amino Acid Motifs
;
Capsid/*chemistry/*metabolism
;
Cryoelectron Microscopy
;
Crystallography, X-Ray
;
DNA, Viral/metabolism
;
Image Processing, Computer-Assisted
;
Models, Molecular
;
Protein Conformation
;
Protein Folding
;
Protein Precursors/*chemistry/*metabolism
;
Protein Structure, Tertiary
;
Protein Subunits
;
Siphoviridae/chemistry/*physiology/ultrastructure
;
Surface Properties
;
*Virus Assembly
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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