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bioRxiv · 10.1101/2021.06.28.450134

Embedded control of cell growth using tunable genetic systems

Fusco, V.·Salzano, D.·Fiore, D.·di Bernardo, M.
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Abstract

We present an embedded feedback control strategy to control the density of a bacterial population, allowing cells to self-regulate their growth rate so as to reach a desired density at steady state. We consider a static culture condition, where cells are provided with a limited amount of space and nutrients. The control strategy is built using a tunable expression system (TES), which controls the production of a growth inhibitor protein, complemented with a quorum sensing mechanism for the sensing of the population density. We show on a simplified population-level model that the TES endows the control system with additional flexibility by allowing the set-point to be changed online. Finally, we validate the effectiveness of the proposed control strategy by means of realistic in silico experiments conducted in BSim, an agent-based simulator explicitly designed to simulate bacterial populations, and we test the robustness of our design to disturbances and parameters variations due, for instance, to cell-to-cell variability.

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Fusco, V., Salzano, D., Fiore, D., di Bernardo, M.. 2021-06-28. Embedded control of cell growth using tunable genetic systems. https://doi.org/10.1101/2021.06.28.450134

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