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bioRxiv · 10.1101/2022.06.13.495893

Dynamic cybergenetic control of bacterial co-culturecomposition via optogenetic feedback

Gutierrez, J.·Kumar, S.·Khammash, M.
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Abstract

Communities of microbes play important roles in natural environments and hold great potential for deploying division-of-labor strategies in synthetic biology and bioproduction. However, the difficulty of controlling the composition of microbial consortia over time hinders their optimal use in many applications. Here, we present a fully automated, high-throughput platform that combines real-time measurements and computer-controlled optogenetic modulation of bacterial growth to implement precise and robust compositional control of a two-strain E. coli community. Additionally, we develop a general framework for dynamic modeling of synthetic genetic circuits in the physiological context of E. coli and use a host-aware model to determine the optimal control parameters of our closed-loop compositional control system. Our platform succeeds in stabilizing the strain ratio of multiple parallel co-cultures at arbitrary levels and in changing these targets over time, opening the door for the implementation of dynamic compositional programs in synthetic bacterial communities.

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Gutierrez, J., Kumar, S., Khammash, M.. 2022-06-14. Dynamic cybergenetic control of bacterial co-culturecomposition via optogenetic feedback. https://doi.org/10.1101/2022.06.13.495893

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