The E. coli Vsr Endonuclease
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.
KeywordsMicrofuge Tube Multicopy Plasmid Nonsense Codon Sonication Buffer Talon Metal Affinity Resin
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