Table 1

Contribution of S. aureus mutT homologs to spontaneous mutagenesis in E. coli ΔmutT

StrainaMutation frequency (95% CI)bFold differencec
ΔmutT-vec10.0 × 10−7 (7.5–13.9)1.00
ΔmutT-vec(mutT)0.3 × 10−7 (0.2–0.7)0.03***
ΔmutT-vec(429)9.5 × 10−7 (8.2–13.3)0.95
ΔmutT-vec(1593)8.0 × 10−7 (6.5–11.6)0.80
ΔmutT-vec(1782)6.5 × 10−7 (5.7–10.6)0.65
ΔmutT-vec(1913)8.8 × 10−7 (6.1–18.9)0.88
ΔmutT-vec(2791)0.7 × 10−7 (0.7–4.6)0.07***
WT0.8 × 10−7 (0.3–2.1)0.08***
ΔmutT20.7 × 10−7 (13.2–32.4)2.07*
  • a WT, E. coli BW25113; vec, pWSK29. Data in parentheses indicate 8325 mutT homolog (number) or mutT from E. coli MG1655 (mutT) insertion in pWSK29.

  • b Mutation frequency values represent the medians from 10 independent determinations of RifR CFU/viable CFU. Data in parentheses indicate the 95% confidence interval (CI).

  • c Fold difference values were calculated with respect to the median for the ΔmutT-vec strain. *, P ≤ 0.05; ***, P ≤ 0.001 (for comparisons to the WT based on the Mann-Whitney test).