Graphic view of the experimental evolution setup.

Three flasks labeled A, B, and C in red (striated caps) were inoculated with both yeast and bacteria whereas the other three flasks labeled D, E, and F in black (caps with no fill) were inoculated with yeast only (controls). The cultures were successively passaged for at most passages depending on the strain (see Table 2). After every 10 passages, cultures were withdrawn and karyotyped using pulse field gel electrophoresis (PFGE). Those that underwent genomic rearrangements were then phenotyped using a high-throughput micro-cultivation instrument, Bioscreen C (Oy Growth Curves, Finland).