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Updated: Mar 30, 2026
05:42
Quantitative PCR of T7 Bacteriophage from Biopanning
Published on: September 27, 2018
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Encapsidated conformation of bacteriophage T7 DNA
M E Cerritelli1, N Cheng, A H Rosenberg
1Laboratory of Structural Biology, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA.
Cell
|November 5, 1997
Summary
Researchers used cryo-electron microscopy to reveal how T7 bacteriophage DNA is packaged. The study shows the DNA is spooled in six coaxial shells within the phage head, forming a quasi-crystalline structure.
Area of Science:
- Structural biology
- Virology
- Molecular biology
Background:
- Bacteriophages are viruses that infect bacteria.
- Understanding viral DNA packaging is crucial for molecular biology and nanotechnology.
- T7 bacteriophage is a well-studied model organism.
Purpose of the Study:
- To elucidate the structural organization of encapsidated T7 DNA.
- To visualize the DNA packing within the T7 phage head.
Main Methods:
- Cryo-electron microscopy (cryo-EM) for high-resolution imaging.
- Advanced image processing techniques.
- Computer modeling for data corroboration.
Main Results:
- Identified two preferred views of T7 phage heads: axial and side views.
- Axial views showed concentric rings, indicating DNA spooled around an axis.
- Side views revealed punctate arrays, consistent with quasi-crystalline packing.
Conclusions:
- T7 DNA is organized into approximately six coaxial shells.
- DNA exhibits quasi-crystalline packing within the phage head.
- The connector protein's core complex may guide DNA packaging.
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