Fig. 2

Ferromagnetic and anti-ferromagnetic configurations of coupled, bi-stable synthetic gene networks. a Schematic representation of ferromagnetic and anti-ferromagnetic interactions between two neighboring cells. The states, defined by the expression of red (mCherry2 labeled as “RFP” for simplicity) or green (sfGFP, labeled as “GFP” for simplicity) fluorescent proteins, are determined by mutually inhibiting repressors R1 and R2. Cell states are coupled, in ferromagnetic and anti-ferromagnetic configurations, with neighboring cells by diffusive signals C6 and C12. b Gene network arrangement of ferromagnetic and anti-ferromagnetic systems in C6 and C12 states. Ferromagnetic and anti-ferromagnetic systems are composed of a ferromagnetic or anti-ferromagnetic vector and a reporter vector. LasR-C12 and LuxR-C6 complexes were omitted for simplicity. c–f Red and green fluorescent protein synthesis rate of E. coli cells carrying ferromagnetic (c, d) and anti-ferromagnetic (e, f) systems, grown in liquid medium supplemented with different concentrations of C6HSL (left) and C12HSL (right). Points and error bars correspond to the mean of the fluorescent protein synthesis rates normalized by its maximum value reached in each system and the standard deviation of 4 biological replicates, while lines correspond to the fitting of Eq. 2