Investigating the Potential of Division of Labor in Synthetic Bacterial Communities for the Production of Violacein

With advancements in synthetic biology and metabolic engineering, microorganisms can now be engineered to perform increasingly complex functions, which may be limited by the resources available in individual cells. Introducing heterologous metabolic pathways introduces both genetic burden due to the competition for cellular transcription and translational machinery, as well as metabolic burden due to the redirection of metabolic flux from the native metabolic pathways. Division of labor in synthetic microbial communities offers a promising approach to enhance metabolic efficiency and resilience in bioproduction. By distributing complex metabolic pathways across multiple subpopulations, the resource competition and metabolic burden imposed on an individual cell are reduced, potentially enabling more efficient production of target compounds. Violacein is a high-value pigment with antitumor properties that exemplifies such a challenge due to its complex bioproduction pathway, imposing a significant metabolic burden on host cells. In this study, we investigated the benefits of division of labor for violacein production by splitting the violacein bioproduction pathway between two subpopulations of <i><i>Escherichia coli</i></i>-based synthetic communities. We tested several pathway splitting strategies and reported that splitting the pathway into two subpopulations expressing VioABE and VioDC at a final composition of 60:40 yields a 2.5-fold increase in violacein production as compared to a monoculture. We demonstrated that the coculture outperforms the monoculture when both subpopulations exhibit similar metabolic burden levels, resulting in comparable growth rates, and when both subpopulations are present in sufficiently high proportions.