Fig. 1

IS insertion rates vary across different bacterial genomes. IS insertion rates of various bacterial genomes are compared to the IS insertion rates in the wild-type and 12 DNA repair deficient mutants of E. coli K12 MG1655 reported previously [21]. This figure plotted the number of observed IS insertions (y-axis) versus the total number of generations (x-axis) in a group of MA lines originating from the same founder strain in a single experiment. While all the MA experiments on E. coli K12 MG1655 exhibited a linear relationship between the number of insertions and the number of generations, suggesting a constant IS insertion rate per generation across these lines, only in some of the other E. coli strains and bacterial species studied here, similar IS insertion rates were observed. In contrast, much higher rates were observed in wild-type D. radiodurans BAA-816 and E. coli REL4536 grown in the anaerobical condition, whereas much lower rates are observed in E. coli ED1a and IAI1 strains.For the linear regression, the dotted line shows the 95% confidence interval boundaries