Figure 3
From: Programming the group behaviors of bacterial communities with synthetic cellular communication
Synchronization of genetic oscillations by communication-based circuits. (A) A QS-based gene circuit that synchronizes the oscillation of gene expression in an isogenic bacterial population. The oscillation is enabled by positive feedback, arising from the self-activation of AHL synthesis, and negative feedback, mediated by the AHL-degrading gene aiiA. The coupling of the two feedback loops results in robust oscillations of gene expression of an entire bacterial population (thousands of cells). (B) An advanced gene circuit modified from (A) that enables large-scale synchronization of oscillatory gene expression. In addition to the coupled positive and negative feedback in (A), an additional positive feedback loop is introduced by coupling the production of thermally unstable H2O2 by NADH dehydrogenase (ndh) with AHL biosynthesis, leading to global oscillation synchronization of millions of cells.