Department of Pediatrics, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093-0760, USA.
Department of Chemical and Biomolecular Engineering, The Johns Hopkins University, 3400 North Charles Street, Baltimore, MD, 21218, USA.
Nat Commun. 2020 Jul 30;11(1):3803. doi: 10.1038/s41467-020-17612-8.
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-secreting Synechococcus elongatus with heterotrophic Escherichia coli K-12, Escherichia coli W, Yarrowia lipolytica, or Bacillus subtilis. Model simulations reveae metabolic exchanges that sustain the heterotrophs in minimal media devoid of any organic carbon source, pointing to S. elongatus-E. coli K-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.
由光养生物和异养生物组成的微生物群落为可持续生物技术提供了巨大的前景。这些群落的成功应用依赖于合适伙伴的选择。在这里，我们构建了四个群落代谢模型来指导菌株选择，将光合、蔗糖分泌的 Synechococcus elongatus 与异养 Escherichia coli K-12、Escherichia coli W、Yarrowia lipolytica 或 Bacillus subtilis 进行配对。模型模拟揭示了在缺乏任何有机碳源的最小培养基中维持异养生物的代谢交换，指出 S. elongatus-E. coli K-12 是最活跃的群落。对这一对的通量预测进行实验验证，证实了代谢相互作用和潜在的生产能力。合成群落绕过了成员特异性的代谢瓶颈（例如组氨酸和运输相关反应），并补偿了致命的遗传特征，从致死性敲除中恢复了高达 27%的能力。该研究为使用光养生物伙伴进行合理设计具有优化生长可持续性的合成群落提供了一个强大的建模框架。
