Project description:Understand the mechanisms of evolution in large-scale bio-production by tracking population dynamics leading to production decline in mevalonic acid-producing Escherichia coli. Industrial bioproduction entails growth of the production host to large bioreactors (e.g. 1-300 m3). This may put the organism at risk for generating non-producing subpopulations of genetic heterogeneity, which is not phenotypically detected at lab-scale (e.g. 2 L). To study these dynamics, we experimentally simulated these growth durations by passing mevalonic acid-producing E. coli to maintain the populations in exponential growth for 45 generations.
Project description:Populations of engineered metabolite-producing microorganisms are prone to evolutionary production declines during industrial-scale cultivations. In this study, we develop a synthetic product addiction system in E coli that addicts mevalonic acid production cells to mevalonic acid. Through experimentally simuluated long-term fermentation, we investigate how product-addicted organisms remain stable and avoid formation of genetic subpopulations of fit, non-producing cells.