How microbes adapt to (variable) environments through regulation and evolution
Microbiologist Iraes Rabbers’ research revolves around the themes of fitness and adaptation. How well do organisms, in this case the microorganisms Escherichia coli and Lactococcus cremoris, fit in their environment and how much offspring are they able to produce to achieve ‘evolutionary success’?
In order to produce more offspring (than their competitors), they will need to adapt to their environment and make the best use of the available resources. Here, Rabbers and her colleagues study the adaptive properties of these two model microbes, both on short timescales (where optimal expression tuning of protein production plays a major role) and longer timescales (where adaptive evolution through mutation and selection comes into play).
Rabbers demonstrated that E. coli is remarkably capable of reaching optimal fitness throughout a wide variety of (even atypical) environments. This is interesting, as it demonstrates the adaptability of this organism in the short term. Apparently long-term evolutionary adaptive processes for specific environments are not necessary - it seems to have optimized its flexibility.
In addition, the study shows that overflow metabolism (characterized by a biphasic growth pattern), which was previously viewed as fast but inefficient, might not be so inefficient after all. It also leads to maximization of cell number yield during the second growth phase, in addition to the fast growth during the first growth phase. This is another example of how flexibility (in this case of a metabolic strategy) can be optimal.
More information on the