Reconstitution of the very short patch repair pathway from Escherichia coli

J Biol Chem. 2012 Sep 21;287(39):32953-66. doi: 10.1074/jbc.M112.384321. Epub 2012 Jul 30.

Abstract

The Escherichia coli very short patch (VSP) repair pathway corrects thymidine-guanine mismatches that result from spontaneous hydrolytic deamination damage of 5-methyl cytosine. The VSP repair pathway requires the Vsr endonuclease, DNA polymerase I, a DNA ligase, MutS, and MutL to function at peak efficiency. The biochemical roles of most of these proteins in the VSP repair pathway have been studied extensively. However, these proteins have not been studied together in the context of VSP repair in an in vitro system. Using purified components of the VSP repair system in a reconstitution reaction, we have begun to develop an understanding of the role played by each of these proteins in the VSP repair pathway and have gained insights into their interactions. In this report we demonstrate an in vitro reconstitution of the VSP repair pathway using a plasmid DNA substrate. Surprisingly, the repair track length can be modulated by the concentration of DNA ligase. We propose roles for MutL and MutS in coordination of this repair pathway.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adenosine Triphosphatases / genetics
  • Adenosine Triphosphatases / metabolism
  • DNA Ligase ATP
  • DNA Ligases / genetics
  • DNA Ligases / metabolism
  • DNA Polymerase I / genetics
  • DNA Polymerase I / metabolism
  • DNA Repair / physiology*
  • DNA, Bacterial / genetics
  • DNA, Bacterial / metabolism*
  • Endodeoxyribonucleases / genetics
  • Endodeoxyribonucleases / metabolism
  • Escherichia coli / genetics
  • Escherichia coli / metabolism*
  • Escherichia coli Proteins / genetics
  • Escherichia coli Proteins / metabolism
  • MutL Proteins
  • MutS DNA Mismatch-Binding Protein / genetics
  • MutS DNA Mismatch-Binding Protein / metabolism

Substances

  • DNA, Bacterial
  • Escherichia coli Proteins
  • MutL protein, E coli
  • DNA Polymerase I
  • Endodeoxyribonucleases
  • vsr endonuclease
  • Adenosine Triphosphatases
  • MutL Proteins
  • MutS DNA Mismatch-Binding Protein
  • MutS protein, E coli
  • DNA Ligases
  • DNA Ligase ATP