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. 2017 Jul 20;13(7):e1006733. doi: 10.1371/journal.pgen.1006733

Fig 5. Persistent oxidized guanine in DNA is required for MBR.

Fig 5

Overproduction of MutM 8-oxo-dG DNA glycosylase and MutT 8-oxo-GTP diphosphatase nucleotide triphosphate pool sanitizer reduces MBR in the Tet assay. Overproduction of MutM and MutT reduced TetR mutant frequency 82% ± 9.7% and 91% ± 5.3%, respectively compared with the vector control (p = 0.0015 and 0.0002, Student’s 2-tailed t-test). The data indicate, first, that 8-oxo-dG in DNA is required for MBR, second, that the effects of 8-oxo-dG on MBR result mainly from incorporation of 8-oxo-dG from the dNTP pool, and third, that 8-oxo-dG must remain in DNA for MBR to occur, because if 8-oxo-dG is removed by the MutM DNA glycosylase, MBR is reduced. * significantly different from the empty vector control (pVector) at the 5% level. Strains used: No DSB, SMR10798; no DSB pVector, PJH3237; DSB, SMR10866; DSB pVector, PJH3232; DSB rpoS pVector PJH3240; DSB dinB50 pVector PJH3231; DSB pMutM, PJH3233; DSB pMutT, PJH3256.