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T4 Bacteriophage and E. coli Interaction in the Murine Intestine: A Prototypical Model for Studying Host-Bacteriophage Dynamics In Vivo
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Multiple-Tailed T4 Bacteriophage

K O Smith1, M Trousdale

  • 1Department of Virology and Epidemiology, Baylor University College of Medicine, Houston, Texas.

Journal of Bacteriology
|September 1, 1965
PubMed

Insights

Researchers observed T4 bacteriophage particles with multiple tails, with double-tailed forms appearing at high frequencies. Attempts to isolate pure lines of these unusual phage particles were unsuccessful.

Area of Science:

  • Microbiology
  • Virology
  • Molecular Biology

Background:

  • Bacteriophages are viruses that infect bacteria.
  • T4 bacteriophage is a well-studied model organism in molecular biology.
  • Morphological variations in viruses can provide insights into their replication and assembly processes.

Purpose of the Study:

  • To investigate the occurrence and characteristics of multiple-tailed T4 bacteriophage particles.
  • To differentiate between true multiple-tailed particles and artifacts caused by particle superposition.
  • To determine the conditions favoring the production of multiple-tailed phage.

Main Methods:

  • Microscopic examination of T4 bacteriophage preparations.
  • Experimental design to exclude the possibility of particle superposition.
  • Controlled inoculation of Escherichia coli with T4 phage at varying multiplicities.
  • Culturing of phage under different bacterial growth phases.

Main Results:

  • T4 phage particles with multiple tails were observed, with double-tailed particles occurring at frequencies up to 10%.
  • Triple- and quadruple-tailed particles were extremely rare.
  • Highest frequencies of multiple-tailed phage were produced by Escherichia coli in the logarithmic growth phase, inoculated at a multiplicity of approximately 2.
  • All attempts to isolate pure lines of multiple-tailed phage were unsuccessful.

Conclusions:

  • Multiple-tailed T4 bacteriophage particles are a genuine morphological variant, not an artifact of superposition.
  • Specific growth conditions, particularly bacterial growth phase and phage multiplicity, influence the production of these variants.
  • The inability to isolate pure lines suggests potential instability or complex genetic/assembly mechanisms involved in multiple-tail formation.

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