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Genome-wide Gene Deletions in Streptococcus sanguinis by High Throughput PCR
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Genome-wide Gene Deletions in Streptococcus sanguinis by High Throughput PCR

Published on: November 23, 2012

Extrachromosomal gene systems in Streptococcus mutans

F L Macrina, S S Virgili, C L Scott

    Advances in Experimental Medicine and Biology
    |January 1, 1978
    PubMed

    Insights

    This study investigated plasmids in Streptococcus mutans strains. While plasmids were found in human and rat strains, they did not confer significant phenotypes but showed potential for gene cloning applications.

    Area of Science:

    • Microbiology
    • Molecular Biology
    • Genetics

    Background:

    • Streptococcus mutans are bacteria associated with human and animal oral health.
    • Extrachromosomal DNA elements like plasmids can influence bacterial traits.
    • Understanding plasmid presence and function in S. mutans is crucial.

    Purpose of the Study:

    • To characterize plasmids in human and rat-derived Streptococcus mutans strains.
    • To assess whether identified plasmids confer clinically or ecologically relevant phenotypes.
    • To evaluate the utility of these plasmids for gene cloning.

    Main Methods:

    • Screening of S. mutans strains for plasmid DNA.
    • Plasmid size determination using molecular weight markers.
    • Restriction endonuclease digestion (Hind III, Bam HI) of plasmids.
    • Analysis of plasmid-associated phenotypes.

    Main Results:

    • Plasmids were detected in 4 of 86 human S. mutans strains (3.6 Mdal) and 2 of 13 rat S. mutans strains (2.3 Mdal and 2.5 Mdal).
    • No significant clinical or ecological phenotypes were associated with these plasmids.
    • The 3.6 Mdal plasmid was cleaved once by Hind III and Bam HI, indicating suitability for cloning.

    Conclusions:

    • Plasmids are present in some S. mutans strains but do not appear to confer important phenotypes.
    • The characterized 3.6 Mdal plasmid is a potential tool for gene cloning applications in molecular biology.

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