Table 1.

Increased mutation frequencies at the hprt and tk loci after infection with pks+ E. coli

LocusCellsInfectionMF ± SE × 10−5
hprt CHOControl1.68 ± 1.17
E. coli pks 2.89 ± 2.02
E. coli pks+ 11.40 ± 1.16*
E. coli clbA 1.54 ± 1.11
E. coli clbA + pclbA 11.80 ± 1.14*
tk CHOControl31.7 ± 2.44
E. coli pks 29.1 ± 3.18
E. coli pks+ 48.3 ± 2.02*
hprt HCT-116Control1.52 ± 0.18
E. coli pks 1.52 ± 0.27
E. coli pks+ 3.58 ± 0.20*
  • CHO and HCT-116 cells were infected (MOI = 20) or left uninfected, then grown for 7 or 3 d before plating with 6-thioguanine or trifluorothymidine to select for hprt or tk mutants, respectively.

  • *P < 0.05, x 2- Mc Nemar test compared with control, pks , and clbA. MF, mutation frequency.