The E. coli Vsr Endonuclease

Assaying Activity In Vitro and In Vivo
  • Claire G. Cupples
  • Georgina Macintyre
Part of the Methods in Molecular Biology™ book series (MIMB, volume 152)


The primary function of the Vsr endonuclease of Escherichia coli is to initiate repair of T/G mismatches that arise from deamination of 5-methylcytosine to thymine (reviewed in 1). By making a nick 5′ of the T, Vsr provides a site for DNA polymerase I to start the removal of the mismatched base, along with several nucleotides on its 3′ side. Resynthesis of the missing bases by the polymerase restores the correct C.G basepair and completes the process of very short patch (VSP) repair.


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Copyright information

© Humana Press Inc. 2000

Authors and Affiliations

  • Claire G. Cupples
    • 1
  • Georgina Macintyre
    • 1
  1. 1.Department of BiologyConcordia UniversityMontréalCanada

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