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Phage Phenomics: Physiological Approaches to Characterize Novel Viral Proteins
Published on: June 11, 2015
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Integrative structural analysis of Pseudomonas phage DEV reveals a genome ejection motor
Ravi K Lokareddy1, Chun-Feng David Hou2, Francesca Forti3
1Department of Biochemistry and Molecular Genetics, University of Alabama at. Birmingham (UAB), 1825 University Blvd, Birmingham, AL, USA.
Nature Communications
|October 1, 2024
Summary
This study reveals the complete structure of the Pseudomonas phage DEV, detailing its tail fibers and virion-associated RNA polymerase (vRNAP). These findings illuminate the infection mechanism and conserved genome ejection apparatus in Schitoviridae phages.
Area of Science:
- Bacteriophage biology
- Structural biology
- Microbial genomics
Background:
- DEV is a lytic phage belonging to the Schitoviridae family, known to infect Pseudomonas.
- Its genome contains genes for essential components like virion-associated RNA polymerase (vRNAP).
Purpose of the Study:
- To elucidate the complete architecture of the DEV phage.
- To understand the role of its components in host infection and genome delivery.
- To investigate the conservation of its genome ejection mechanism within the Schitoviridae family.
Main Methods:
- Cryo-electron microscopy localized reconstruction
- Biochemical assays
- Genetic knockouts
Main Results:
- The complete structure of DEV, including capsid and tail components, was determined.
- DEV long tail fibers are crucial for infecting Pseudomonas aeruginosa but not strains with truncated lipopolysaccharides.
- DEV vRNAP is part of a conserved three-gene operon, likely forming a genome ejection motor.
Conclusions:
- The structural and functional insights into DEV provide a model for understanding Schitoviridae phage-host interactions.
- The proposed genome ejection apparatus is conserved across the Schitoviridae family.
- DEV serves as a key model for studying phage infection and genome delivery mechanisms.
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