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Characterization of infectious deoxyribonucleic acid from temperature Bacillus subtilis bacteriophage phi105

L Rutberg, B Rutberg

    Journal of Virology
    |May 1, 1970
    PubMed

    Insights

    Researchers studied infectious deoxyribonucleic acid (DNA) from phi105 phage and bacteria. They found that infectious phage DNA behaves differently depending on its source and degrades quickly after infection.

    Area of Science:

    • Molecular Biology
    • Virology
    • Bacteriology

    Background:

    • Bacteriophages, like phi105, are viruses that infect bacteria.
    • Lysogenic bacteria harbor phage DNA integrated into their genome.
    • Understanding phage DNA behavior is crucial for molecular biology and virology.

    Purpose of the Study:

    • To characterize the sedimentation properties of infectious deoxyribonucleic acid (DNA) from phi105 phage particles.
    • To investigate the infectivity and sedimentation of prophage DNA in lysogenic bacteria.
    • To analyze the behavior of infectious vegetative phage DNA during bacterial infection.

    Main Methods:

    • Phenol extraction of infectious deoxyribonucleic acid (DNA).
    • Sedimentation analysis in neutral sucrose gradients.
    • Assessment of DNA infectivity post-extraction and during infection.

    Main Results:

    • Infectious phi105 phage DNA sedimented similarly to mature phage DNA in neutral sucrose.
    • Prophage DNA infectivity was linked to heterogeneous, fast-sedimenting material.
    • Infectious vegetative phage DNA sedimented faster than mature DNA and was rapidly inactivated post-infection.

    Conclusions:

    • The physical state and sedimentation characteristics of infectious phi105 DNA vary depending on its origin (phage particle, prophage, or vegetative form).
    • Infectious vegetative phage DNA undergoes rapid degradation or conversion to a less infectious state within the host bacterium.

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