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The phage phi29 membrane protein p16.7, involved in DNA replication, is required for efficient ejection of the viral

Martín Alcorlo1, Víctor González-Huici, José M Hermoso

  • 1Instituto de Biología Molecular Eladio Viñuela, Centro de Biología Molecular Severo Ochoa, Universidad Autónoma, Canto Blanco, 28049 Madrid, Spain.

Journal of Bacteriology
|May 29, 2007
PubMed

Insights

Bacteriophage phi29 DNA ejection involves active protein participation. Protein p16.7 is essential for the second, pulling step of viral DNA entry into Bacillus subtilis cells.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Virology

Background:

  • In vivo phage DNA ejection is an active process involving viral and host proteins.
  • Bacteriophage phi29 DNA ejection occurs in two steps: an initial push and a subsequent pull.
  • Protein p17, ejected during the first step, is known to be required for the second DNA pull step.

Purpose of the Study:

  • To investigate the role of membrane protein p16.7 in the DNA ejection mechanism of Bacillus subtilis bacteriophage phi29.
  • To determine if p16.7 is involved in the active pulling step of phage DNA entry.

Main Methods:

  • Analysis of bacteriophage phi29 DNA ejection in the presence and absence of functional p16.7.
  • Investigating the requirement of p16.7 for the second DNA pull step.

Main Results:

  • The study demonstrates that protein p16.7 is required for efficient execution of the second DNA pull step.
  • This finding indicates a dual role for p16.7, beyond its known function in membrane-associated DNA replication.

Conclusions:

  • Bacteriophage phi29 DNA ejection is an active, protein-mediated process.
  • Membrane protein p16.7 plays a critical role in the efficient completion of phage DNA entry into the host cell.

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