Seeing the Portal in Herpes Simplex Virus Type 1 B Capsids

Structural Computational Biology and Molecular Biophysics Program, Baylor College of Medicine, Houston, Texas 77030, USA.
Journal of Virology (Impact Factor: 4.44). 02/2011; 85(4):1871-4. DOI: 10.1128/JVI.01663-10
Source: PubMed

ABSTRACT Resolving the nonicosahedral components in large icosahedral viruses remains a technical challenge in structural virology. We have used the emerging technique of Zernike phase-contrast electron cryomicroscopy to enhance the image contrast of ice-embedded herpes simplex virus type 1 capsids. Image reconstruction enabled us to retrieve the structure of the unique portal vertex in the context of the icosahedral capsid and, for the first time, show the subunit organization of a portal in a virus infecting eukaryotes. Our map unequivocally resolves the 12-subunit portal situated beneath one of the pentameric vertices, thus removing uncertainty over the location and stoichiometry of the herpesvirus portal.

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Available from: Frazer Rixon, Sep 28, 2015
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    • "When portal proteins of phages or herpesviruses are expressed at high levels, polymorphisms are commonly encountered in the number of subunits in the ring. However, it appears that, in both cases, only 12-mers are assembled into capsids (Lurz et al. 2001; Rochat et al. 2011). Crystal structures of several phage portals, of varying size, have been determined (Simpson et al. 2001; Lebedev et al. 2007; Olia et al. 2011). "
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