UMMS Affiliation

Department of Biochemistry and Molecular Pharmacology



Document Type


Medical Subject Headings

*Adenosine Triphosphatases; Bacterial Proteins; Base Sequence; DNA; DNA Repair; *DNA-Binding Proteins; Endodeoxyribonucleases; Escherichia coli; *Escherichia coli Proteins; Molecular Sequence Data; MutS DNA Mismatch-Binding Protein; Mutation; Nucleic Acid Heteroduplexes; Protein Binding; Protein Conformation


Vsr DNA mismatch endonuclease is the key enzyme of very short patch (VSP) DNA mismatch repair and nicks the T-containing strand at the site of a T-G mismatch in a sequence-dependent manner. MutS is part of the mutHLS repair system and binds to diverse mismatches in DNA. The function of the mutL gene product is currently unclear but mutations in the gene abolish mutHLS -dependent repair. The absence of MutL severely reduces VSP repair but does not abolish it. Purified MutL appears to act catalytically to bind Vsr to its substrate; one-hundredth of an equivalent of MutL is sufficient to bring about a significant effect. MutL enhances binding of MutS to its substrate 6-fold but does so in a stoichiometric manner. Mutational studies indicate that the MutL interaction region lies within the N-terminal 330 amino acids and that the MutL multimerization region is at the C-terminal end. MutL mutant monomeric forms can stimulate MutS binding.

Rights and Permissions

Originally published: Nucleic Acids Res. 1998 Feb 15;26(4):948-53. Link to article on publisher's website

Related Resources

Link to Article in PubMed

PubMed ID




To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.