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Following Cell-fate in E. coli After Infection by Phage Lambda
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Phage integration and chromosome structure. A personal history

Allan Campbell1

  • 1Department of Biological Sciences, Stanford University, Stanford, CA 94305-5020, USA. AMC@stanford.edu

Annual Review of Genetics
|May 4, 2007
PubMed

Insights

A 1962 model proposed lambda phage DNA integrates into bacterial chromosomes via circularization and recombination. This integration model, involving specific DNA sites, contrasted with prior theories of lateral attachment.

Area of Science:

  • Molecular Biology
  • Genetics
  • Microbiology

Background:

  • The integration of bacteriophage lambda into bacterial genomes is a fundamental process in molecular biology.
  • Previous models suggested lateral attachment rather than direct chromosomal insertion.

Purpose of the Study:

  • To present a model for lambda prophage integration into the bacterial chromosome.
  • To summarize the experimental evidence leading to the proposed model.

Main Methods:

  • Genetic characterization of specialized transducing phages (lambda-gal).
  • Recombinational rescue of conditionally lethal mutations.
  • Analysis of DNA circularization and reciprocal recombination.

Main Results:

  • Proposed a two-step integration model: DNA circularization followed by site-specific recombination.
  • Demonstrated that integration results in a cyclic permutation of gene order.
  • Discovered conditionally lethal mutations serendipitously.

Conclusions:

  • The proposed model provided a novel mechanism for bacteriophage integration.
  • This work advanced the understanding of genetic recombination and phage-host interactions.

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