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Updated: Aug 11, 2026

Preparation of the Mgm101 Recombination Protein by MBP-based Tagging Strategy
11:40

Preparation of the Mgm101 Recombination Protein by MBP-based Tagging Strategy

Published on: June 25, 2013

Direct repetition of a 1.2 Md DNA sequence is involved in site-specific recombination by the P1 plasmid R68

J Leemans, R Villarroel, B Silva

    Gene
    |September 1, 1980
    PubMed

    Insights

    A novel insertion sequence, IS8, was identified in the R68.45 plasmid, contributing to plasmid formation and site-specific recombination. This discovery enhances understanding of bacterial plasmid dynamics and genetic elements.

    Area of Science:

    • Molecular Biology
    • Genetics
    • Microbiology

    Background:

    • The R68.45 plasmid, a mutant derivative of the R68 plasmid, exhibits unique genetic characteristics.
    • Understanding the genetic makeup of plasmids is crucial for comprehending bacterial adaptation and evolution.

    Purpose of the Study:

    • To characterize a significant DNA insertion within the R68.45 plasmid.
    • To elucidate the role of this insertion in plasmid formation and recombination events.

    Main Methods:

    • Analysis of the DNA sequence and structure of the R68.45 plasmid.
    • Identification and characterization of repetitive DNA elements and foreign DNA fragments.

    Main Results:

    • A 1.5 Md DNA insertion was identified in the R68.45 plasmid, near the kanamycin-resistance region.
    • This insertion comprises a 1.2 Md DNA repeat (IS8) flanking a 0.3 Md foreign DNA fragment.
    • The IS8 element is implicated in the formation of R'68.45 plasmids and site-specific recombination in RP4.

    Conclusions:

    • The 1.2 Md DNA fragment, designated IS8, functions as an insertion sequence.
    • IS8 plays a critical role in the generation of R'68.45 plasmids and influences site-specific recombination.
    • This finding contributes to the understanding of mobile genetic elements and their impact on plasmid evolution.

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