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Updated: Jul 4, 2026
06:10
Following Cell-fate in E. coli After Infection by Phage Lambda
Published on: October 14, 2011
DNA poised for release in bacteriophage phi29
Jinghua Tang1, Norman Olson, Paul J Jardine
1Department of Chemistry and Biochemistry, University of California-San Diego, La Jolla, CA 92093, USA.
Structure (London, England : 1993)
|June 13, 2008
Summary
Researchers reveal the first 3D structure of the bacteriophage phi29 virus, detailing its protein and DNA interactions. This provides new insights into virus assembly and DNA packaging mechanisms.
Area of Science:
- Structural Biology
- Virology
- Biophysics
Background:
- Bacteriophage phi29 is a well-studied model organism for DNA packaging.
- Understanding viral structure is crucial for deciphering infection mechanisms and developing antiviral strategies.
Purpose of the Study:
- To determine the first asymmetric, three-dimensional reconstruction of the mature bacteriophage phi29.
- To elucidate the detailed interactions between viral proteins and DNA.
- To gain insight into the mechanics of virus assembly and DNA retention.
Main Methods:
- Asymmetric, three-dimensional reconstruction
- Subnanometer resolution imaging
- Cryo-electron microscopy (implied)
Main Results:
- Revealed detailed asymmetric interactions and conformational dynamics of phi29 protein and DNA components.
- Observed significant rearrangement of the dodecameric head-tail connector protein during assembly.
- Identified specific interactions between tightly packed double-stranded DNA (dsDNA) and viral proteins.
- Discovered a novel toroidal dsDNA structure (approximately 60Å diameter) within the connector-lower collar cavity, suggesting high internal pressure.
Conclusions:
- The bacteriophage phi29 structure provides unprecedented detail on viral assembly mechanics.
- The observed DNA toroid structure highlights extreme DNA deformation under pressure.
- This toroidal structure may play a role in retaining DNA within the capsid before injection.
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