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Title: Synthetic microbial communities of heterotrophs and phototrophs facilitate sustainable growth
Abstract

Microbial communities comprised of phototrophs and heterotrophs hold great promise for sustainable biotechnology. Successful application of these communities relies on the selection of appropriate partners. Here we construct four community metabolic models to guide strain selection, pairing phototrophic, sucrose-secretingSynechococcus elongatuswith heterotrophicEscherichia coliK-12,Escherichia coliW,Yarrowia lipolytica, orBacillus subtilis. Model simulations reveae metabolic exchanges that sustain the heterotrophs in minimal media devoid of any organic carbon source, pointing toS. elongatus-E. coliK-12 as the most active community. Experimental validation of flux predictions for this pair confirms metabolic interactions and potential production capabilities. Synthetic communities bypass member-specific metabolic bottlenecks (e.g. histidine- and transport-related reactions) and compensate for lethal genetic traits, achieving up to 27% recovery from lethal knockouts. The study provides a robust modelling framework for the rational design of synthetic communities with optimized growth sustainability using phototrophic partners.

Authors:
; ; ; ; ; ; ; ;
Award ID(s):
1804733 1804671 1804187
Publication Date:
NSF-PAR ID:
10177368
Journal Name:
Nature Communications
Volume:
11
Issue:
1
ISSN:
2041-1723
Publisher:
Nature Publishing Group
Sponsoring Org:
National Science Foundation
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