Fig. 2.

The sensitivity of wild-type E. coli cells to killing by ampicillin, norfloxacin, and kanamycin is reduced when incorporation of 8-oxo-dG is minimized. A. Overproduction of the 8-oxo-dGTP sanitizer MutT (blue) in wild-type MG1655 cells was sufficient to significantly reduce the sensitivity of cells to the bactericidal effects of all three classes of drugs compared to the vector control (black). B. Overproduction of the alternative 8-oxo-dGTP sanitizer RibA (yellow) in MG1655 cells is also sufficient to reduce the sensitivity of cells to ampicillin and norfloxacin, but not kanamycin, probably due to its instability (Fig. S5). C. Overproduction of the 8-OH-dATP sanitizer NudB (green) does not reduce the antibiotic sensitivity. D. A mutant strain which lacks the two Y-family DNA polymerases, and expresses an anti-mutator replicative polymerase (dnaE911 ΔdinB ΔumuDC) strain (red) is more resistant to killing by bactericidal antibiotics than wild-type cells (black).