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bioRxiv · 10.1101/2020.02.14.944090

Temperature regulation as a tool to program synthetic microbial community composition

Lin, X. N.·Krieger, A. G.·Zhang, J.
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Abstract

Engineering of synthetic microbial communities is emerging as a powerful new paradigm for performing various industrially, medically, and environmentally important processes. To reach the fullest potential, however, this approach requires further development in many aspects, a key one being regulating the community composition. Here we leverage well established mechanisms in ecology which govern the relative abundance of multi-species ecosystems and develop a new tool for programming the composition of synthetic microbial communities. Using a simple model system consisting of two microorganisms Escherichia coli and Pseudomonas putida, which occupy different but partially overlapping thermal niches, we demonstrate that temperature regulation can be used to enable coexistence and program the community composition. We first investigate a constant temperature regime and show that different temperatures lead to different community compositions. Next, we invent a new cycling temperature regime and show that it can dynamically tune the microbial community, achieving a wide range of compositions depending on parameters that are readily manipulatable. Our work provides conclusive proof of concept that temperature regulation is a versatile and powerful tool capable of programming compositions of synthetic microbial communities.

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Lin, X. N., Krieger, A. G., Zhang, J.. 2020-02-14. Temperature regulation as a tool to program synthetic microbial community composition. https://doi.org/10.1101/2020.02.14.944090

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