Biological Assembly 1  

 3D View: Structure

Global Symmetry: Icosahedral - I  (3D View)
Global Stoichiometry: Homo 420-mer - A420 

Biological assembly 1 assigned by authors and generated by (software)

Macromolecule Content

• Total Structure Weight: 197.96 kDa 
• Atom Count: 1792 
• Modelled Residue Count: 1792 
• Deposited Residue Count: 1792 
• Unique protein chains: 1

1IF0

PSEUDO-ATOMIC MODEL OF BACTERIOPHAGE HK97 PROCAPSID (PROHEAD II)

• DOI: 10.2210/pdb1IF0/pdb

• Classification: VIRUS
• Organism(s): Escherichia virus HK97
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2001-04-11 Released: 2001-05-02 
• Deposition Author(s): Conway, J.F., Wikoff, W.R., Cheng, N., Duda, R.L., Hendrix, R.W., Johnson, J.E., Steven, A.C.

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 12.0 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Literature

Virus maturation involving large subunit rotations and local refolding.

Conway, J.F., Wikoff, W.R., Cheng, N., Duda, R.L., Hendrix, R.W., Johnson, J.E., Steven, A.C.

(2001) Science 292: 744-748

• PubMed: 11326105 
• DOI: 10.1126/science.1058069
• Primary Citation of Related Structures:  
  1IF0


• PubMed 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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Related Citations: 

• Topologically Linked Protein Rings in the Bacteriophage HK97 Capsid
  Wikoff, W.R., Liljas, L., Duda, R.L., Tsuruta, H., Hendrix, R.W., Johnson, J.E.
  (2000) Science 289: 2129

• Proteolytic and Conformational Control of Virus Capsid Maturation: The Bacteriophage HK97 System
  Conway, J.F., Duda, R.L., Cheng, N., Hendrix, R.W., Steven, A.C.
  (1995) Science 253: 86

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Organizational Affiliation: 

Laboratory of Structural Biology Research, National Institute of Arthritis, Musculoskeletal and Skin Diseases, Bethesda, MD 20892, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
PROTEIN (MAJOR CAPSID PROTEIN GP5)	A, B, C, D, E, F, G	256	Escherichia virus HK97	Mutation(s): 0  Gene Names: 5
Find proteins for P49861 (Enterobacteria phage HK97) Explore P49861  Go to UniProtKB:  P49861

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 12.0 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2001-04-11 
• Released Date: 2001-05-02 
Deposition Author(s): Conway, J.F., Wikoff, W.R., Cheng, N., Duda, R.L., Hendrix, R.W., Johnson, J.E., Steven, A.C.

Revision History  

• Version 1.0: 2001-05-02
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2019-11-06
  Changes: Data collection, Other