UMass Chan AffiliationsDepartment of Pharmacology and Molecular Toxicology
Amino Acid Sequence
*Escherichia coli Proteins
Molecular Sequence Data
MutS DNA Mismatch-Binding Protein
Nucleic Acid Heteroduplexes
Medicine and Health Sciences
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AbstractThe MutS protein is part of the dam-directed MutHLS mismatch repair pathway in Escherichia coli. We have constructed deletion derivatives in the mutS gene, which retain the P-loop coding region for ATP binding. The mutant proteins were assayed for ATP hydrolysis, heteroduplex DNA binding, heterodimer MutS formation, and the ability to interact with MutL. Dimerization was assayed by expressing His6-tagged wild-type and non-tagged deletion mutant proteins in the same cell and isolating the His6-tagged protein followed by MutS immunoblotting after SDS-polyacrylamide gel electrophoresis. MutS-MutL interaction was measured using the same technique except that the MutL protein carried the His6 tag. Our results indicate that DNA binding ability resides in the N-terminal end of MutS, and dimerization and MutL interactions are located in the C-terminal end. Given the extensive amino acid homology in the MutS family our results with E. coli should be applicable to MutS homologues in other prokaryotes and eukaryotes.
J Biol Chem. 1999 Feb 26;274(9):5948-52.
Permanent Link to this Itemhttp://hdl.handle.net/20.500.14038/42417
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