Specificity and mutagenesis bias of the mycobacterial alternative mismatch repair analyzed by mutation accumulation studies.

ABSTRACT: The postreplicative mismatch repair (MMR) is an almost ubiquitous DNA repair essential for maintaining genome stability. It has been suggested that Mycobacteria have an alternative MMR in which NucS, an endonuclease with no structural homology to the canonical MMR proteins (MutS/MutL), is the key factor. Here, we analyze the spontaneous mutations accumulated in a neutral manner over thousands of generations by Mycobacterium smegmatis and its MMR-deficient derivative (ΔnucS). The base pair substitution rates per genome per generation are 0.004 and 0.165 for wild type and ΔnucS, respectively. By comparing the activity of different bacterial MMR pathways, we demonstrate that both MutS/L- and NucS-based systems display similar specificity and mutagenesis bias, revea

SUBMITTER: Castaneda-Garcia A 

PROVIDER: S-EPMC7015689 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature