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Updated: May 25, 2026
08:31
Isolation and Genome Analysis of Single Virions using 'Single Virus Genomics'
Published on: May 26, 2013
Genome gating in tailed bacteriophage capsids.
Paulo Tavares1, Sophie Zinn-Justin, Elena V Orlova
1Unité de Virologie Moléculaire et Structurale, Gif-sur-Yvette, France. tavares@vms.cnrs-gif.fr
Advances in Experimental Medicine and Biology
|February 3, 2012
Summary
Tailed bacteriophages utilize a portal system for genome management, controlled by a gatekeeper. This system ensures stable DNA packaging and controlled release for infection initiation.
Area of Science:
- Virology
- Molecular Biology
- Structural Biology
Background:
- Tailed bacteriophages possess a portal system crucial for viral genome translocation.
- This portal structure is a key component in the assembly and infection cycle of these viruses.
Purpose of the Study:
- To review the mechanisms controlling genome movement through the bacteriophage portal system.
- To highlight recent advances in understanding the portal system's role in genome packaging and release.
Main Methods:
- Review of existing literature on bacteriophage portal systems.
- Analysis of structural and mechanistic data related to genome translocation.
Main Results:
- The portal system, regulated by a genome gatekeeper, controls DNA entry and exit.
- Packaging involves a motor translocating DNA through the portal, terminated by cleavage and motor disassembly.
- Portal closure is achieved via conformational changes or adaptor/stopper proteins, forming a connector for tail assembly.
Conclusions:
- The portal structure is essential for stable viral genome packaging and precise, triggered DNA ejection.
- Recent molecular insights are clarifying the coordination of these critical steps in the phage life cycle.
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