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Published on: April 30, 2010

A possible role for RNA polymerase in the initiation of M13 DNA synthesis

D Brutlag, R Schekman, A Kornberg

    Proceedings of the National Academy of Sciences of the United States of America
    |November 1, 1971
    PubMed

    Insights

    Rifampicin blocks bacteriophage M13 DNA replication by inhibiting bacterial RNA polymerase. This suggests RNA polymerase plays a direct role in initiating DNA replication, possibly by creating a primer.

    Area of Science:

    • Molecular Biology
    • Virology
    • Microbiology

    Background:

    • Bacteriophage M13 DNA replication involves conversion from single-stranded to double-stranded forms.
    • Antibiotics like rifampicin and chloramphenicol are used to study microbial processes.

    Purpose of the Study:

    • To investigate the role of host-cell RNA polymerase in bacteriophage M13 DNA replication.
    • To determine the mechanism by which rifampicin inhibits M13 DNA replication.

    Main Methods:

    • Utilizing bacteriophage M13 and Escherichia coli.
    • Employing antibiotics rifampicin (RNA polymerase inhibitor) and chloramphenicol (protein synthesis inhibitor).
    • Testing M13 DNA replication in a rifampicin-resistant E. coli mutant.

    Main Results:

    • Rifampicin blocked the conversion of single-stranded M13 DNA to its double-stranded form.
    • Chloramphenicol did not block this initial conversion.
    • Rifampicin also inhibited the multiplication of double-stranded M13 DNA, while chloramphenicol had a lesser effect.
    • M13 DNA replication was not inhibited by rifampicin in a resistant E. coli mutant.

    Conclusions:

    • The inhibition of M13 DNA replication by rifampicin is due to its interaction with bacterial RNA polymerase.
    • Bacterial RNA polymerase likely plays a direct role in initiating M13 DNA replication, potentially via primer RNA synthesis.

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