WGS of P. aeruginosa evolved either in presence or absence of a protist predator
Six replicate populations of P. aeruginosa NRB were propagated in Neff medium either alone (media-evolved; ME) or in the presence of Tetrahymena thermophila (predator-evolved; PE) by daily 4% transfers at 35C. At Day 60, each of the six replicate ME and PE populations was split into two parallel populations. One set of populations continued under the original conditions (ME or PE), whereas the second set founded the fluctuating treatments by transferring descendants of the ME populations to predator-containing medium (MP) and descendants of the PE populations to predator-free medium (PM). MP and PM populations alternated between predator-present and predator-free environments every two weeks until Day 180, whereas ME and PE populations continued under their original conditions.