Structural and functional analysis of the MutS C-terminal tetramerization domain.

ABSTRACT: The Escherichia coli DNA mismatch repair (MMR) protein MutS is essential for the correction of DNA replication errors. In vitro, MutS exists in a dimer/tetramer equilibrium that is converted into a monomer/dimer equilibrium upon deletion of the C-terminal 53 amino acids. In vivo and in vitro data have shown that this C-terminal domain (CTD, residues 801-853) is critical for tetramerization and the function of MutS in MMR and anti-recombination. We report the expression, purification and analysis of the E.coli MutS-CTD. Secondary structure prediction and circular dichroism suggest that the CTD is folded, with an alpha-helical content of 30%. Based on sedimentation equilibrium and velocity analyses, MutS-CTD forms a tetramer of asymmetric shape. A single point mutation (D835R) abolishes tetr

SUBMITTER: Manelyte L 

PROVIDER: S-EPMC1636413 | biostudies-literature | 2006

REPOSITORIES: biostudies-literature