Experimental data for Pseudomonas aeruginosa from experimental evolution under different bottleneck sizes and antibiotic selection pressures

We here combined evolution experiments with genomic and genetic analyses to assess whether bottleneck size and antibiotic-induced selection influences the evolutionary path to resistance in pathogenic Pseudomonas aeruginosa, one of the most problematic opportunistic human pathogens. Two sets of evolution experiments were performed across 16 transfers, in which either the aminoglycoside gentamicin or the fluoroquinolone ciprofloxacin were used as antibiotic. The evolutionary response was studied using counts of bacterial cells at the end of each transfer period (i.e., yield) or by calculating the growth rate from regular optical density measurement during the respective transfer periods. For the populations at the end of the evolution experiments, we also determined their antibiotic resistance with the help of standardized dose response curves. Moreover, we performed whole genome sequencing to assess the frequency of variants, which emerged and spread during the evolution experiments. We...