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Bacteriophage PRD1 Capsid Structure: Iterative Combination of Threedimensional Electron Microscopy and X-Ray Crystallography

Published online by Cambridge University Press:  02 July 2020

Carmen San Martin
Affiliation:
The Wistar Institute, 3601 Spruce Street, Philadelphia, Pennsylvania19104
Roger M. Burnett
Affiliation:
The Wistar Institute, 3601 Spruce Street, Philadelphia, Pennsylvania19104
Felix de Haas
Affiliation:
Structural Biology Programme, EMBL, Meyerhofstraβe 1, Postfach 10.2209, 69117 Heidelberg, Germany
Ralph Heinkel
Affiliation:
Structural Biology Programme, EMBL, Meyerhofstraβe 1, Postfach 10.2209, 69117 Heidelberg, Germany
Twan Rutten
Affiliation:
Structural Biology Programme, EMBL, Meyerhofstraβe 1, Postfach 10.2209, 69117 Heidelberg, Germany
Stephen D. Fuller
Affiliation:
Structural Biology Programme, EMBL, Meyerhofstraβe 1, Postfach 10.2209, 69117 Heidelberg, Germany
Sarah J. Butcher
Affiliation:
Institute of Biotechnology and Department of Biosciences, Viikki Biocenter, University of Helsinki, Finland
Dennis H. Bamford
Affiliation:
Institute of Biotechnology and Department of Biosciences, Viikki Biocenter, University of Helsinki, Finland
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Extract

PRD1 is a ds-DNA bacteriophage from the Tectiviridae family with an unusual structural feature: the viral genome is enclosed by a protein-rich membrane, which is in turn enclosed by an external icosahedral protein shell (capsid). Three-dimensional reconstructions from cryo-electron microscopy (cryo-EM) images have revealed the structure of the PRD1 capsid at moderate resolution (28 Å), while X-ray crystallographic studies have recently provided a high resolution (1.85 Å) picture of the major coat protein, P3. We have now combined these results from different imaging methods to obtain a more detailed understanding of the virion organization. The combination has been made in a cyclic process: a preliminary fitting of the atomic structure of P3 to each one of its independent positions in the cryo-EM maps of the capsids provided initial models that could be used to improve the reconstructions; the refined maps then served as a base frame for an optimized fit. This process allows us to study the viral particle structure at “quasi-atomic” resolution.

Type
Electron Cryomicroscopy of Macromolecules
Copyright
Copyright © Microscopy Society of America

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References

1. Bamford, D. H. et al. (1995) Adv. Virus Res. 45, 281319.CrossRefGoogle Scholar

2. Butcher, S. J. et al. (1995) EMBO J. 14, 60786086.CrossRefGoogle Scholar

3. Benson, S. D. et al. (1999) Cell 98, 825833.CrossRefGoogle Scholar

4. Cheng, R. H. et al. (1995) Cell 80, 621630.CrossRefGoogle Scholar

5. Rydman, P. S. et al. (1999) J. Mol. Biol. 291, 575587.CrossRefGoogle Scholar

6. Stewart, P. L. et al. (1993) EMBO J. 12, 25892599.CrossRefGoogle Scholar

7. The authors wish to thank Janne Ravantti and Teemu Kivioja for providing programs used in this work, Marja-Leena Perala for technical assistance, and Stacy D. Benson for help in interpreting the P3 trimer atomic structure. CSM is a recipient of a Human Frontiers Science Program Postdoctoral Fellowship.Google Scholar