1TX9 : gpd prior to capsid assembly

  • Marc C. Morais (Contributor)
  • Megan Fisher (Contributor)
  • Bentley A Fane (Contributor)
  • Michael G. Rossmann (Contributor)



Experimental Technique/Method:X-RAY DIFFRACTION
Release Date:2005-04-26
Deposition Date:2004-06-24
Revision Date:2008-04-30#2011-07-13
Molecular Weight:33644.24
Macromolecule Type:Protein
Residue Count:302
Atom Site Count:2125

The three-dimensional structure of bacteriophage phiX174 external scaffolding protein D, prior to its interaction with other structural proteins, has been determined to 3.3 angstroms by X-ray crystallography. The crystals belong to space group P4(1)2(1)2 with a dimer in the asymmetric unit that closely resembles asymmetric dimers observed in the phiX174 procapsid structure. Furthermore, application of the crystallographic 4(1) symmetry operation to one of these dimers generates a tetramer similar to the tetramer in the icosahedral asymmetric unit of the procapsid. These data suggest that both dimers and tetramers of the D protein are true morphogenetic intermediates and can form independently of other proteins involved in procapsid morphogenesis. The crystal structure of the D scaffolding protein thus represents the state of the polypeptide prior to procapsid assembly. Hence, comparison with the procapsid structure provides a rare opportunity to follow the conformational switching events necessary for the construction of complex macromolecular assemblies.
Date made available2005

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