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bioRxiv · 10.1101/2019.12.23.887331

Killing in response to competition stabilises synthetic microbial consortia

Fedorec, A. J. H.·Karkaria, B. D.·Sulu, M.·Barnes, C. P.
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Abstract

The scale of the biological systems we can engineer is limited by the burden that host cells can bear. Division-of-labour can spread that burden across a community of cells but competitive exclusion inevitably leads to the removal of less fit community members over time. Here, we leverage amensalism and competitive exclusion to stabilise multi-species communities by engineering a strain of Escherichia coli which secretes a toxin in response to competition. We show mathematically and experimentally that such a system can produce stable populations with a composition that is tunable by easily controllable parameters. This is the first system to use competitive exclusion to create a stable two-species consortia and the first to only require the engineering of a single strain.

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Fedorec, A. J. H., Karkaria, B. D., Sulu, M., Barnes, C. P.. 2019-12-25. Killing in response to competition stabilises synthetic microbial consortia. https://doi.org/10.1101/2019.12.23.887331

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