Biological Assembly 1  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report

Global Symmetry: Icosahedral - I  (3D View)
Global Stoichiometry: Homo 180-mer - A180 

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

Macromolecule Content

• Total Structure Weight: 40.00 kDa 
• Atom Count: 2752 
• Modelled Residue Count: 366 
• Deposited Residue Count: 375 
• Unique protein chains: 1

1FR5

PHAGE FR CAPSIDS WITH A FOUR RESIDUE DELETION IN THE COAT PROTEIN FG LOOP

• PDB DOI: 10.2210/pdb1FR5/pdb

• Classification: VIRUS
• Organism(s): Enterobacteria phage fr
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 1998-07-22 Released: 1999-01-13 
• Deposition Author(s): Axblom, C., Tars, K., Fridborg, K., Bundule, M., Orna, L., Liljas, L.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 3.50 Å
• R-Value Work: 0.256 
• R-Value Observed: 0.256 

Literature

Structure of phage fr capsids with a deletion in the FG loop: implications for viral assembly.

Axblom, C., Tars, K., Fridborg, K., Orna, L., Bundule, M., Liljas, L.

(1998) Virology 249: 80-88

• PubMed: 9740779 
• DOI: 10.1006/viro.1998.9279
• Primary Citation of Related Structures:  
  1FR5


• PubMed Abstract: 
  

The loop between beta-strands F and G in the coat protein of small RNA bacteriophages forms the interactions at the fivefold and threefold (quasi-sixfold) icosahedral axes. In many cases, mutations in this region renders the coat protein unable to form capsids. This FG loop has therefore been suggested to be of major importance for the virus assembly process by guiding the assembly and helping to define the correct curvature of the virus shell. We have determined the crystal structure of a phage fr capsid where the coat protein has a four-residue deletion in the FG loop. This mutant retains the ability to form virus capsids of normal size but has a significantly lower temperature stability than the wild type. The structure reveals that the mutated loops are flexible and too short to interact with each other. This seems incompatible with a role of the FG loop in the regulation of capsid size.

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Related Citations: 

• Crystal Structure of Bacteriophage Fr Capsids at 3.5 A Resolution
  Liljas, L., Fridborg, K., Valegard, K., Bundule, M., Pumpens, P.
  (1994) J Mol Biol 244: 279

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Organizational Affiliation: 

Department of Molecular Biology, Uppsala University, Uppsala, S-751 24, Sweden.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
BACTERIOPHAGE FR CAPSID	A, B, C	125	Enterobacteria phage fr	Mutation(s): 0
UniProt
Find proteins for P03614 (Enterobacteria phage fr) Explore P03614  Go to UniProtKB:  P03614

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3.50 Å
• R-Value Work: 0.256 
• R-Value Observed: 0.256 
• Space Group: H 3 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 264.1	α = 90
b = 264.1	β = 90
c = 654.2	γ = 120

Software Package:

Software Name	Purpose
X-PLOR	model building
X-PLOR	refinement
DENZO	data reduction
SCALEPACK	data scaling
X-PLOR	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 1998-07-22 
• Released Date: 1999-01-13 
Deposition Author(s): Axblom, C., Tars, K., Fridborg, K., Bundule, M., Orna, L., Liljas, L.

Revision History  

• Version 1.0: 1999-01-13
  Type: Initial release
  
• Version 1.1: 2008-03-24
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance