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.
Reviewing Editor
- Sjors HW Scheres, MRC Laboratory of Molecular Biology, United Kingdom
Version history
- Received: May 15, 2019
- Accepted: September 9, 2019
- Accepted Manuscript published: September 12, 2019 (version 1)
- Version of Record published: September 18, 2019 (version 2)
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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Further reading
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- Epidemiology and Global Health
Background:
Circulating omega-3 and omega-6 polyunsaturated fatty acids (PUFAs) have been associated with various chronic diseases and mortality, but results are conflicting. Few studies examined the role of omega-6/omega-3 ratio in mortality.
Methods:
We investigated plasma omega-3 and omega-6 PUFAs and their ratio in relation to all-cause and cause-specific mortality in a large prospective cohort, the UK Biobank. Of 85,425 participants who had complete information on circulating PUFAs, 6461 died during follow-up, including 2794 from cancer and 1668 from cardiovascular disease (CVD). Associations were estimated by multivariable Cox proportional hazards regression with adjustment for relevant risk factors.
Results:
Risk for all three mortality outcomes increased as the ratio of omega-6/omega-3 PUFAs increased (all Ptrend <0.05). Comparing the highest to the lowest quintiles, individuals had 26% (95% CI, 15–38%) higher total mortality, 14% (95% CI, 0–31%) higher cancer mortality, and 31% (95% CI, 10–55%) higher CVD mortality. Moreover, omega-3 and omega-6 PUFAs in plasma were all inversely associated with all-cause, cancer, and CVD mortality, with omega-3 showing stronger effects.
Conclusions:
Using a population-based cohort in UK Biobank, our study revealed a strong association between the ratio of circulating omega-6/omega-3 PUFAs and the risk of all-cause, cancer, and CVD mortality.
Funding:
Research reported in this publication was supported by the National Institute of General Medical Sciences of the National Institute of Health under the award number R35GM143060 (KY). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.
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