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Updated: Jun 19, 2026
12:20
Bacterial Artificial Chromosomes: A Functional Genomics Tool for the Study of Positive-strand RNA Viruses
Published on: December 29, 2015
Characterization of DNA conformation inside bacterial viruses
Anton S Petrov1, C Rebecca Locker, Stephen C Harvey
1School of Biology, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
Summary
This study introduces a new formalism to understand DNA organization within bacteriophages. It reveals two key transitions in DNA packaging, leading to global conformations and glasslike dynamics in confined spaces.
Area of Science:
- Structural biology
- Biophysics
- Polymer physics
Background:
- Bacteriophage DNA packaging involves organizing genetic material within confined capsid spaces.
- Previous work showed DNA in bacteriophage phi29 forms folded toroids and in epsilon15 exhibits coaxial organization.
Purpose of the Study:
- To develop a formalism for describing DNA organization during bacteriophage genome packaging.
- To analyze the conformational transitions and dynamics of DNA within bacteriophage capsids.
Main Methods:
- Development of a theoretical formalism to model DNA organization.
- Analysis of DNA conformational transitions and local mobility within confined spaces.
Main Results:
- Identified two consecutive transitions during DNA packaging: global conformation formation (disorder-order) and local DNA mobility loss (glasslike dynamics).
- Demonstrated that bacteriophage systems undergo distinct conformational changes during genome packaging.
Conclusions:
- The proposed formalism provides a framework for studying semiflexible polymer chains in confined environments.
- Bacteriophage genome packaging serves as a model for understanding polymer behavior in restricted spaces.
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