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Updated: Jul 11, 2026
08:31
Isolation and Genome Analysis of Single Virions using 'Single Virus Genomics'
Published on: May 26, 2013
Structure and morphogenesis of bacteriophage T4.
P G Leiman1, S Kanamaru, V V Mesyanzhinov
1Department of Biological Sciences, Purdue University, 915 W State Street, West Lafayette, Indiana 47907-2054, USA. leiman@purdue.edu
Cellular and Molecular Life Sciences : CMLS
|November 20, 2003
Summary
Bacteriophage T4, a complex virus, utilizes tail fibers and a portal protein for host recognition and DNA packaging. This intricate structure is crucial for viral infection and genetic material delivery.
Area of Science:
- Virology
- Molecular Biology
- Structural Biology
Background:
- Bacteriophage T4 is a highly complex virus with over 40 proteins forming its mature virion.
- The virion comprises a protein shell, genomic DNA, a tail, and fibers essential for host interaction.
- The tail facilitates DNA delivery into the host cell, while fibers and tail proteins mediate host recognition and attachment.
Purpose of the Study:
- To elucidate the structural and functional roles of key components in Bacteriophage T4.
- To understand the mechanism of host cell recognition and DNA delivery by the phage tail.
- To investigate the function of the portal protein in DNA packaging during head assembly.
Main Methods:
- Structural analysis of Bacteriophage T4 virion components.
- Biochemical assays to study protein interactions and functions.
- Genetic studies to assess the role of specific proteins in the viral life cycle.
Main Results:
- Bacteriophage T4 fibers and tail proteins act as host cell recognition sensors for attachment.
- The phage tail serves as a conduit for delivering viral DNA into the host cytoplasm.
- A dodecameric portal protein at the unique head vertex is critical for viral DNA packaging.
Conclusions:
- The complex structure of Bacteriophage T4, particularly its tail and portal protein, is essential for its infectivity.
- Understanding these components provides insights into viral assembly and DNA packaging mechanisms.
- This research contributes to the broader knowledge of viral-host interactions and DNA transport in viruses, including herpesviruses.
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