Modeling Evolutionary Dynamics of *E. coli* in the Long-Term Stationary Phase

Bacteria can maintain a near-constant population size for years without an external food source in a state known as the long-term stationary phase (LTSP). However, they do not hibernate - instead, they survive by recycling the nutrients of dead bacteria, creating a dynamic and evolving environment. In the Cluzel Lab at Harvard, we experimentally introduced an evolutionary pressure in E. coli by transforming a plasmid with overexpressed nonessential proteins, including YFP, into the bacteria to increase their protein burden, and followed the state of the plasmid using the fluorescent reporter. We also developed a system of differential equations to model the system: the introduction of oscillating protein burdens led to coexistence between proteins of different average burdens, which could allow us to better explain past experimental observations. This work was supported by the Program for Research in Science and Engineering (PRISE) at Harvard College.