1I9W

CRYSTAL STRUCTURE OF THE FUSION GLYCOPROTEIN E1 FROM SEMLIKI FOREST VIRUS

• PDB DOI: https://doi.org/10.2210/pdb1I9W/pdb

• Classification: VIRAL PROTEIN
• Organism(s): Semliki Forest virus
• Mutation(s): No 


• Deposited: 2001-03-21 Released: 2002-04-06 
• Deposition Author(s): Lescar, J., Roussel, A., Wien, M.W., Navaza, J., Fuller, S.D., Wengler, G., Wengler, G., Rey, F.A.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 3.00 Å
• R-Value Free: 
  0.344 (Depositor), 0.470 (DCC) 
• R-Value Work: 
  0.275 (Depositor), 0.470 (DCC) 

Literature

The Fusion glycoprotein shell of Semliki Forest virus: an icosahedral assembly primed for fusogenic activation at endosomal pH.

Lescar, J., Roussel, A., Wien, M.W., Navaza, J., Fuller, S.D., Wengler, G., Wengler, G., Rey, F.A.

(2001) Cell 105: 137-148

• PubMed: 11301009 
• DOI: https://doi.org/10.1016/s0092-8674(01)00303-8
• Primary Citation of Related Structures:  
  1I9W


• PubMed Abstract: 
  

  Semliki Forest virus (SFV) has been extensively studied as a model for analyzing entry of enveloped viruses into target cells. Here we describe the trace of the polypeptide chain of the SFV fusion glycoprotein, E1, derived from an electron density map at 3.5 A resolution and describe its interactions at the surface of the virus. E1 is unexpectedly similar to the flavivirus envelope protein, with three structural domains disposed in the same primary sequence arrangement. These results introduce a new class of membrane fusion proteins which display lateral interactions to induce the necessary curvature and direct budding of closed particles. The resulting surface protein lattice is primed to cause membrane fusion when exposed to the acidic environment of the endosome.

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Organizational Affiliation: 

Laboratoire de Génétique des Virus, CNRS-UPR 9053, 1, Avenue de la Terrasse, 91198 Gif-sur-Yvette Cedex, France.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 42.62 kDa 
• Atom Count: 369 
• Modelled Residue Count: 369 
• Deposited Residue Count: 390 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
FUSION PROTEIN E1	A	390	Semliki Forest virus	Mutation(s): 0
UniProt
Find proteins for P03315 (Semliki forest virus) Explore P03315  Go to UniProtKB:  P03315

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3.00 Å
• R-Value Free:  0.344 (Depositor), 0.470 (DCC) 
• R-Value Work:  0.275 (Depositor), 0.470 (DCC) 

Space Group: P 6₄ 2 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 79.46	α = 90
b = 79.46	β = 90
c = 334.76	γ = 120

Software Package:

Software Name	Purpose
MLPHARE	phasing
CNS	refinement
DENZO	data reduction
CCP4	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 2002-04-06 
Deposition Author(s): Lescar, J., Roussel, A., Wien, M.W., Navaza, J., Fuller, S.D., Wengler, G., Wengler, G., Rey, F.A.

Revision History  

• Version 1.0: 2002-04-06
  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: 2017-02-08
  Changes: Structure summary
• Version 1.4: 2024-02-07
  Changes: Data collection, Database references