New complexities of SOS-induced "untargeted" mutagenesis in Escherichia coli as revealed by mutation accumulation and whole-genome sequencing.

ABSTRACT: When its DNA is damaged, Escherichia coli induces the SOS response, which consists of about 40 genes that encode activities to repair or tolerate the damage. Certain alleles of the major SOS-control genes, recA and lexA, cause constitutive expression of the response, resulting in an increase in spontaneous mutations. These mutations, historically called "untargeted", have been the subject of many previous studies. Here we re-examine SOS-induced mutagenesis using mutation accumulation followed by whole-genome sequencing (MA/WGS), which allows a detailed picture of the types of mutations induced as well as their sequence-specificity. Our results confirm previous findings that SOS expression specifically induces transversion base-pair substitutions, with rates averaging about 60-fold above wi

SUBMITTER: Niccum BA 

PROVIDER: S-EPMC7299831 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature