Bacteria that become "persisters" can survive stress (such as starvation or application of antibiotics), but cannot reproduce. Persisters consume less food, making more food available for other bacteria. Did the persistence trait evolve because it helps individuals to survive stress, or because it is advantageous to bacterial groups, especially close relatives? Computer models and experiments with different mixtures of harmless bacteria under different conditions will be used to investigate this issue. Bacteria that fluoresce different colors will be used, so that they can be distinguished for measurements.
Diseases caused by persister bacteria are more difficult to cure because they are hard to kill, even with antibiotics that kill active individuals of the same strains. This research may suggest how hospital conditions and treatments affect the rapid evolution of bacterial persistence, even within a single patient. In addition, if persistence is in fact an example of individuals sacrificing their own success for the common good of their relatives, then this system can be used to study the evolution of cooperation, doing experiments in days that would take decades with multicellular organisms. This research will provide training opportunities for high school and undergraduate students.
