4. Conclusion
In this study, we investigated adaptation at the single-cell level and
showed that an isogenic, recombinant S. cerevisiae strain
differentiated into three subpopulations: (1) cells that drastically
reduced insulin production (23 %), (2) cells with reduced enzymatic
capacity of the central carbon metabolism (46 %), (3) cells that
exhibited pseudohyphal growth (31 %). This indicates that the bulk
adaptive outcome is a mixed response composed of at least three apparent
subpopulations emerged as a response to the selective pressure of the
chemostat and the burden of the heterologous insulin production.