Fig. 1

Engineering microbial consortia compared to single strains. A In monoculture, a single engineered strain expresses all enzymes to carry out an entire metabolic pathway. Engineering a microbial community enables division of labor, where each strain expresses one enzyme for the pathway. Intercellular communication (red arrows) may also be synthetically introduced. B Signal processing for biosensing or biocomputing. In a single strain, all genetic circuits are implemented in the same strain. In a consortium, the signalling circuits are distributed across populations of the community. C In monoculture, the culture is homogeneous so there will be no competition or interactions modifying the growth dynamics of the population (left). A challenge in consortia engineering is maintaining a stable co-culture due to interactions between strains. Often, certain strains of a microbial community dominate the environment leading other strains to extinction (middle), unless the community is engineered to account for this (right)