Isolation and characterization of the Escherichia coli mutL gene product

J Biol Chem. 1989 Jan 15;264(2):1000-4.


The Escherichia coli mutL gene product has been purified to near homogeneity from an overproducing clone. The mutL locus encodes a polypeptide of 70,000 daltons as determined by denaturing gel electrophoresis. The native molecular weight of MutL protein as calculated from the sedimentation coefficient of 5.5 S and Stokes radius of 61 A is 139,000 daltons, indicating that MutL exists as a dimer in solution. In addition to its ability to complement methyl-directed DNA mismatch repair in mutL-deficient cell-free extracts, DNase I protection experiments demonstrate that the purified MutL protein interacts with the MutS-heteroduplex DNA complex in the presence of ATP.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Bacterial Proteins / isolation & purification*
  • Chromatography / methods
  • Chromatography, Gel / methods
  • DNA Repair
  • Durapatite
  • Electrophoresis, Polyacrylamide Gel
  • Escherichia coli / genetics*
  • Genes*
  • Genes, Bacterial*
  • Hydroxyapatites
  • Indicators and Reagents
  • Molecular Weight


  • Bacterial Proteins
  • Hydroxyapatites
  • Indicators and Reagents
  • Durapatite