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Some mutant phages produced directly by Bacillus megatherium 899a with their rate of occurrence

J S MURPHY

    The Journal of Experimental Medicine
    |December 1, 1954
    PubMed

    Insights

    Bacterial phage mutants are produced directly by Bacillus megatherium 899a. This study found no evidence that phage mutation requires passage through sensitive cells, supporting direct mutation in bacterial cultures.

    Area of Science:

    • Microbiology
    • Virology
    • Genetics

    Background:

    • Bacterial viruses, or bacteriophages, can undergo mutation.
    • Understanding the mechanism of phage mutation is crucial for molecular biology.

    Purpose of the Study:

    • To investigate the rate and types of phage T mutants produced by Bacillus megatherium 899a.
    • To determine if phage mutation requires passage through a sensitive bacterial cell.

    Main Methods:

    • Cultures of Bacillus megatherium 899a were grown in two different media: peptone (high reinfection probability) and asparagine (low reinfection probability).
    • Phage T mutants were isolated and characterized.
    • 396 individual mutant plaques were classified into at least 18 types.

    Main Results:

    • Little difference was observed in the number or types of mutants produced between the two media.
    • The overall mutant ratio was approximately 1:2000.
    • Individual mutants appeared at rates ranging from 1:7000 to less than 1:100,000.

    Conclusions:

    • Phage mutants are produced directly by Bacillus megatherium 899a.
    • Mutation does not necessitate intermediate passage through a sensitive bacterial cell.
    Keywords:
    BACILLUSBACTERIOPHAGE

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