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Characterization of plasmids determining hemolysin and bacteriocin production in Streptococcus faecalis 5952

D R Oliver, B L Brown, D B Clewell

    Journal of Bacteriology
    |May 1, 1977
    PubMed

    Insights

    Two plasmids, pOB1 and pOB2, were isolated from Streptococcus faecalis. pOB1 confers transmissibility and hemolytic activity, while pOB2 produces a bacteriocin inhibiting specific S. faecalis strains.

    Area of Science:

    • Microbiology
    • Molecular Biology

    Background:

    • Streptococcus faecalis harbors various plasmids that influence its characteristics.
    • Understanding plasmid-mediated traits is crucial for studying bacterial genetics and pathogenicity.

    Purpose of the Study:

    • To isolate and characterize plasmids from Streptococcus faecalis strain 5952.
    • To determine the functions and properties of the isolated plasmids, pOB1 and pOB2.

    Main Methods:

    • Plasmid isolation from Streptococcus faecalis strain 5952.
    • Molecular weight determination of isolated plasmids.
    • Assays for hemolytic activity and bacteriocin production.
    • Transmissibility studies of plasmids.

    Main Results:

    • Two plasmids, pOB1 (46 x 10^6 Da) and pOB2 (28 x 10^6 Da), were successfully isolated.
    • pOB1 demonstrated transmissibility and conferred hemolytic activity.
    • pOB2 was found to produce a bacteriocin specifically inhibitory to S. faecalis strains carrying the pAM539 plasmid.

    Conclusions:

    • Plasmids pOB1 and pOB2 possess distinct genetic determinants within Streptococcus faecalis.
    • pOB1 contributes to hemolytic activity and horizontal gene transfer.
    • pOB2 encodes a bacteriocin with specific inhibitory action against certain S. faecalis strains.

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