Emergent genetic oscillations in a synthetic microbial consortium

TLDR

Synthetic biology seeks to build cooperative microbial systems that display population‑level behaviors by using cellular signaling to regulate gene expression across multiple cell types. The study constructs a synthetic microbial consortium of activator and repressor strains. The consortium employs two orthogonal signaling molecules to coordinate gene expression across the activator and repressor strains. When cultured together, the activator and repressor strains produced emergent population‑level oscillations, with certain network topologies yielding more robust rhythms, demonstrating that genetic engineering of multiple cooperative strains can program complex population dynamics.

Abstract

A challenge of synthetic biology is the creation of cooperative microbial systems that exhibit population-level behaviors. Such systems use cellular signaling mechanisms to regulate gene expression across multiple cell types. We describe the construction of a synthetic microbial consortium consisting of two distinct cell types—an "activator" strain and a "repressor" strain. These strains produced two orthogonal cell-signaling molecules that regulate gene expression within a synthetic circuit spanning both strains. The two strains generated emergent, population-level oscillations only when cultured together. Certain network topologies of the two-strain circuit were better at maintaining robust oscillations than others. The ability to program population-level dynamics through the genetic engineering of multiple cooperative strains points the way toward engineering complex synthetic tissues and organs with multiple cell types.