Fig. 4

Mutation rates test. Mutation rates in the laboratory evolved strains and its parentals were determined by a modified Luria-Delbrück fluctuation test, employing the MSS-MLE and the LC methods in the estimation of the number of mutants. The mutation rate is higher in the PB12 and PB13 strains as compared to JM101 and PB11 strains. Mutation frequency was also calculated (Freq). All the results have a confidence interval of 95 %. A detailed table is available in the Additional file 2: Table S2