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: 4.65). 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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