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Mutants of a bacteriophage of Bacillus megatherium

J S MURPHY

    The Journal of Experimental Medicine
    |December 1, 1952
    PubMed

    Insights

    Researchers isolated new bacteriophage strains from lysogenic bacteria by repeated transfers. This method successfully identified four distinct plaque types of Bacillus megatherium phage, expanding the known diversity.

    Area of Science:

    • Microbiology
    • Bacteriology
    • Virology

    Background:

    • Lysogenic bacteria harbor bacteriophages (phages) within their cells.
    • Bacteriophage C was used in experiments with Bacillus megatherium.
    • Understanding phage-host interactions is crucial in microbial genetics.

    Purpose of the Study:

    • To isolate and characterize novel bacteriophage strains from lysogenic Bacillus megatherium.
    • To investigate the genetic adaptability of bacteriophages during lysogenic cycles.
    • To expand the known diversity of Bacillus megatherium phages.

    Main Methods:

    • Repeated subculturing of lysogenic Bacillus megatherium in nutrient media (5% peptone or asparagine).
    • Isolation of bacteriophages based on plaque morphology and host interactions.
    • Characterization of isolated phage strains through plaque typing and mixed infection experiments.

    Main Results:

    • Successfully isolated lysogenic bacteria producing distinct bacteriophage strains.
    • Identified four unique plaque types of Bacillus megatherium phage.
    • Demonstrated the isolation of C and T analogues for each strain, increasing the total known plaque types to eight.

    Conclusions:

    • Repeated transfers in specific media can select for bacteriophage variants capable of lysogenic adjustment.
    • The study successfully expanded the characterized plaque types of Bacillus megatherium phage.
    • Attempts to isolate double-mutant phages through crosses of single-mutant phages were unsuccessful.
    Keywords:
    BACILLUSBACTERIOPHAGE

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