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Enhanced Reduced Representation Bisulfite Sequencing for Assessment of DNA Methylation at Base Pair Resolution
13:47

Enhanced Reduced Representation Bisulfite Sequencing for Assessment of DNA Methylation at Base Pair Resolution

Published on: February 24, 2015

[Separation of modification methylation and restriction enzymes from Shigella sonnei 47]

I M Kartashova, I I Nikol'skaia, S S Debov

    Molekuliarnaia Genetika, Mikrobiologiia I Virusologiia
    |April 1, 1985
    PubMed

    Insights

    Researchers purified DNA modifying enzymes, MSsoI and MSsoII methylases, from Shigella sonnei. These enzymes protect DNA from restriction by RSsoI and RSsoII endonucleases, crucial for host specificity.

    Area of Science:

    • Molecular Biology
    • Microbiology
    • Enzymology

    Background:

    • Shigella sonnei possesses two DNA host specificity systems: SsoI and SsoII.
    • Understanding these systems requires isolating and characterizing their associated enzymes.

    Purpose of the Study:

    • To separate modifying methylases (MSsoI, MSsoII) and restriction endonucleases (RSsoI, RSsoII) from Shigella sonnei.
    • To investigate the modification functions of MSsoI and MSsoII methylases.

    Main Methods:

    • Enzyme separation using column chromatography on phenyl-sepharose and isoelectrofocusing on ampholines.
    • Analysis of methylation and restriction enzyme separation possibilities on various sorbents.
    • In vitro studies on the protective functions of purified methylases.

    Main Results:

    • A successful scheme was developed to separate methylases and restriction endonucleases.
    • Purified MSsoI and MSsoII methylases were obtained, free from restriction endonucleases.
    • DNA methylated by MSsoI or MSsoII demonstrated resistance to RSsoI and RSsoII restriction.

    Conclusions:

    • The study successfully isolated and characterized MSsoI and MSsoII methylases.
    • Demonstrated the protective role of MSsoI and MSsoII methylation against cognate restriction enzymes.
    • Provides a foundation for further research into Shigella sonnei DNA modification and restriction systems.

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