Adaptation of E. coli to low concentrations of spectinomycin
E. coli K-12 MG1655 was allowed to evolve in spectinomycin at 0.1x MIC for 20 generations. Adapted clones that showed a change in MIC (resistant, SPMR) or increase in fitness without change in MIC (tolerant, adapted, SPMA) were subjected to genome sequencing.