Bacterial EndoMS/NucS acts as a clamp-mediated mismatch endonuclease to prevent asymmetric accumulation of replication errors.

ABSTRACT: Mismatch repair (MMR) systems based on MutS eliminate mismatches originating from replication errors. Despite extensive conservation of mutS homologues throughout the three domains of life, Actinobacteria and some archaea do not have genes homologous to mutS. Here, we report that EndoMS/NucS of Corynebacterium glutamicum is the mismatch-specific endonuclease that functions cooperatively with a sliding clamp. EndoMS/NucS function in MMR was fully dependent on physical interaction between EndoMS/NucS and sliding clamp. A combination of endoMS/nucS gene disruption and a mutation in dnaE, which reduced the fidelity of DNA polymerase, increased the mutation rate synergistically and confirmed the participation of EndoMS in replication error correction. EndoMS specifically cleaved G/T, G/G and T/

SUBMITTER: Takemoto N 

PROVIDER: S-EPMC6159521 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature