The MutS protein plays an important role in the DNA mismatch repair system. Mutations in the mutS gene can lead to genome instability and ultimately cell malfunction. Here we have established a method for identifying functional defective mutants of MutS by random mutation and rifampicin screening. Some novel functional sites in MutS were identified. The MutS mutant strains were analyzed using surface plasmon resonance, gel filtration and far-western methods to determine the molecular mechanisms behind the DNA mismatch repair function of MutS.
