2XD8 : Capsid structure of the infectious Prochlorococcus Cyanophage P-SSP7

  • Xiangan Liu (Contributor)
  • Qinfen Zhang (Contributor)
  • Kazuyoshi Murata (Contributor)
  • Matthew L. Baker (Contributor)
  • Matthew B. Sullivan (Massachusetts Institute of Technology) (Contributor)
  • Caroline Fu (Contributor)
  • Matthew T. Dougherty (Contributor)
  • Michael F. Schmid (Contributor)
  • Marcia S. Osburne (Contributor)
  • Sallie W. Chisholm (Contributor)
  • Wah Chiu (Contributor)



Experimental Technique/Method:ELECTRON MICROSCOPY
Release Date:2010-06-16
Deposition Date:2010-04-30
Revision Date:2013-03-20
Molecular Weight:276459.47
Macromolecule Type:Protein
Residue Count:2625
Atom Site Count:2541

Podovirus P-SSP7 infects Prochlorococcus marinus, the most abundant oceanic photosynthetic microorganism. Single-particle cryo-electron microscopy yields icosahedral and asymmetrical structures of infectious P-SSP7 with 4.6-A and 9-A resolution, respectively. The asymmetric reconstruction reveals how symmetry mismatches are accommodated among five of the gene products at the portal vertex. Reconstructions of infectious and empty particles show a conformational change of the 'valve' density in the nozzle, an orientation difference in the tail fibers, a disordering of the C terminus of the portal protein and the disappearance of the core proteins. In addition, cryo-electron tomography of P-SSP7 infecting Prochlorococcus showed the same tail-fiber conformation as that in empty particles. Our observations suggest a mechanism whereby, upon binding to the host cell, the tail fibers induce a cascade of structural alterations of the portal vertex complex that triggers DNA release.
Date made available2010

Cite this