Kaitlin E Creamer, Frederick S Ditmars, Preston J Basting, Karina S Kunka, Issam N Hamdallah, Sean P Bush, Zachary Scott, Amanda He, Stephanie R Penix, Alexandra S Gonzales, Elizabeth K Eder, Dominic W Camperchioli, Adama Berndt, Michelle W Clark, Kerry A Rouhier, Joan L Slonczewski
Escherichia coli K-12 W3110 grows in the presence of membrane-permeant organic acids that can depress cytoplasmic pH and accumulate in the cytoplasm. We conducted experimental evolution by daily diluting cultures in increasing concentrations of benzoic acid (up to 20 mM) buffered at external pH 6.5, a pH at which permeant acids concentrate in the cytoplasm. By 2,000 generations, clones isolated from evolving populations showed increasing tolerance to benzoate but were sensitive to chloramphenicol and tetracycline...
January 15, 2017: Applied and Environmental Microbiology