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The host outer membrane proteins OmpA and OmpC are associated with the Shigella phage Sf6 virion

Haiyan Zhao1, Reuben D Sequeira, Nadezhda A Galeva

  • 1Department of Molecular Biosciences, University of Kansas, 1200 Sunnyside Avenue, Lawrence, KS 66045, USA. zhaohy@ku.edu

Virology
|November 13, 2010
PubMed

Insights

Bacteriophage Sf6 assembly utilizes host Shigella flexneri outer membrane proteins (OMPs) OmpA and OmpC. These OMPs may play a role in phage morphogenesis, revealing a novel phage:host linkage.

Area of Science:

  • Microbiology
  • Structural Biology
  • Virology

Background:

  • The role of host cell components in bacteriophage assembly is not fully understood.
  • Previous studies indicated unidentified proteins within the bacteriophage Sf6 virion.

Purpose of the Study:

  • To identify the unknown proteins found in bacteriophage Sf6 virions.
  • To investigate the potential role of host cell components in bacteriophage assembly.

Main Methods:

  • Tandem mass spectrometry was employed to identify proteins within the Sf6 virion.
  • Transmission electron cryo-microscopy was used to determine the structure of Sf6.

Main Results:

  • Two host outer membrane proteins (OMPs), OmpA and OmpC from Shigella flexneri, were identified in the Sf6 virion.
  • Cryo-EM structural analysis revealed densities on the inner surface of the Sf6 capsid, consistent with OMP beta-barrel domains.
  • The location of these densities suggests a role in Sf6 morphogenesis, similar to phage-encoded cementing proteins.

Conclusions:

  • Host OMPs (OmpA and OmpC) are incorporated into the bacteriophage Sf6 virion.
  • This finding establishes a new phage:host linkage involving OMPs and suggests their involvement in phage assembly.
  • This adds to existing knowledge of phage-encoded porins in some bacteriophages.

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