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Understanding the Impact of Temperate Bacteriophages on Their Lysogens Through Transcriptomics
09:23

Understanding the Impact of Temperate Bacteriophages on Their Lysogens Through Transcriptomics

Published on: January 5, 2024

Factors controlling the production of lysogenic cultures of B. megatherium

J H NORTHROP

    The Journal of General Physiology
    |May 1, 1961
    PubMed

    Insights

    Bacterial virus infection and lysogeny in Bacillus megatherium depend on virus particle numbers and culture media. Optimizing conditions significantly increases lysogenic colony formation and virus production.

    Area of Science:

    • Microbiology
    • Bacteriology
    • Virology

    Background:

    • Lysogeny, the integration of viral DNA into a host genome, is a critical aspect of bacterial-viral interactions.
    • Bacillus megatherium serves as a model organism for studying lysogenic cycles and phage-bacterial relationships.

    Purpose of the Study:

    • To investigate the factors influencing the development of lysogenic colonies in Bacillus megatherium.
    • To determine the impact of infecting virus particle concentration, type, and culture medium on lysogeny.

    Main Methods:

    • Infecting Bacillus megatherium cells with varying concentrations of T virus particles (from strains 899 and KM).
    • Culturing infected cells in different media (yeast extract peptone, asparagine).
    • Monitoring cell disintegration, virus particle production, and lysogenic colony formation.

    Main Results:

    • High T virus concentrations (≥100 particles) led to cell lysis and minimal lysogeny, while low concentrations (1-few particles) resulted in high virus yield and moderate lysogeny.
    • T phage from lysogenic KM cultures induced significantly higher lysogeny rates compared to the original 899 virus.
    • Transferring infected cells to asparagine medium post-infection dramatically increased lysogenic colony yield (10^6 per 10^7 cells), even after initial virus production.

    Conclusions:

    • Lysogenic colony formation in Bacillus megatherium is highly sensitive to the multiplicity of infection and the composition of the culture medium.
    • Specific phage strains and environmental conditions can be manipulated to enhance lysogenic transformation.
    • Long-term cultivation of lysogenic strains can lead to the evolution of new virus types.
    Keywords:
    BACILLUS/culture

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