Abstract:
Synthetic biology aims at engineering biological systems with new functionalities, with applications ranging from personalized health treatments to bioremediation and the production of biofuels and drugs in bioreactors. This is made possible by designing artificial genetic circuits and embedding them into living cells, such as bacteria or yeast, changing their natural behavior, that is by modifying when and how much genes are expressed to produce proteins or other chemicals of interest. However, the level of complexity and the functions of such engineered genetic circuits are limited by intrinsic factors in the host cells, such as excessive metabolic burden, competition of limited resources and incompatible chemical reactions. To overcome these limitations, a promising strategy is to distribute the required functionalities among multiple cell populations, forming a microbial consortium, so that each cell strain embeds a smaller subset of engineered gene networks. However, this comes at the cost of engineering more complex systems in which each actor involved, i.e., a microbial species, cooperates with the others, sharing resources for their growth and communicates to maintain the community in health and the rate of bioreactions at the desired level. Therefore, the new challenge is to develop new feedback control strategies inside the microbial community to guarantee, at the same time, cooperation, communication, stable coexistence between the species involved, and reliable and robust bioproduction.