The frequency of accumulation of Phe⁺ mutants in <i>P. putida</i> strains carrying the pheA+C test system at different chromosomal locations^a.

aAverage numbers of Phe+ mutants per day and total number of mutants for day 9 calculated per 1×107 cells with 95% confidence intervals are shown. The results with at least 6 independent populations of each strain are presented. bStrains carrying the mutational target gene opposite to the direction of the movement of replisome in the chromosome are indicated in bold. cBased on the comparison of the frequency of Phe+ mutations accumulated for day 9 statistically significantly different (P<0.05) homogeneity groups (a–d) appeared.