Electron cryo-microscopy of Bacteriophage PR772 reveals the elusive vertex complex and the capsid architecture
Abstract
Bacteriophage PR772, a member of the Tectiviridae family, has a 70-nm diameter icosahedral protein capsid that encapsulates a lipid membrane, dsDNA, and various internal proteins. An icosahedrally averaged CryoEM reconstruction of the wild-type virion and a localized reconstruction of the vertex region reveal the composition and the structure of the vertex complex along with new protein conformations that play a vital role in maintaining the capsid architecture of the virion. The overall resolution of the virion is 2.75 Å, while the resolution of the protein capsid is 2.3 Å. The conventional penta-symmetron formed by the capsomeres is replaced by a large vertex complex in the pseudo T=25 capsid. All the vertices contain the host-recognition protein, P5; two of these vertices show the presence of the receptor-binding protein, P2. The 3D structure of the vertex complex shows interactions with the viral membrane, indicating a possible mechanism for viral infection.
Data availability
CryoEM Density maps and atomic models that support the findings of this study have been deposited in the Electron Microscopy Database and the Protein Databank with the accession codes EMD-4461 (Whole particle reconstruction), EMD-4462 (Vertex Complex), EMD-10237 (Localized reconstruction of the penton region), EMD-10238 (Focused Classification of the penton region) and PDB ID 6Q5U (Atomic model of the asymmetric unit).
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High resolution electron cryo-microscopy structure of the bacteriophage PR772Electron Microscopy Database, 4461.
Article and author information
Author details
Funding
Vetenskapsrådet (828-2012-108)
- Janos Hajdu
Vetenskapsrådet (628-2008-1109)
- Janos Hajdu
Vetenskapsrådet (822-2010-6157)
- Janos Hajdu
Vetenskapsrådet (822-2012-5260)
- Janos Hajdu
Knut och Alice Wallenbergs Stiftelse (KAW-2011.081)
- Janos Hajdu
European Research Council (ERC-291602)
- Janos Hajdu
Vetenskapsrådet (349-2011-6488)
- Janos Hajdu
Vetenskapsrådet (2015-06107)
- Janos Hajdu
European Structural and Investment Funds (CZ.02.1.01/0.0/0.0/15_003/0000447)
- Janos Hajdu
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Reddy et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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