Fig. 2. Computational model of inter-strain communication in defined spatial environments.

a Model schematic depicting the physical and biological processes represented by the model equations (Supplementary Methods). b The model RFP_p steady-states decrease with the distance from the sender strain. The blue dashed line represents the maximum RFP_p steady-state concentration for a 2 μm interaction channel. The gray dashed line denotes 1% of the maximum steady-state RFP_p concentration. Data points (squares) represent experimental measurements and error bars denote 1 SD from the mean. c Heat map of the simulated RFP_p time delays for diffusible signal molecules spanning a broad range of diffusion rates (D₁) and binding affinities of LuxRAHL to the RFP_p promoter (K_RFP). The circle represents the estimated parameters based on experimental data. d RFP_p steady-state dose response as a function of AHL for different K_RFP and K_LuxR values. The dashed curve represents the dose response of the parameterized model based on the experimental data. Inset denotes representative simulations of RFP_p for different interaction channel lengths. The RFP_p steady states for each interaction channel length (colored marker styles) were computed for ara = 10. e Steady-state RFP_p dose response as a function of AHL for two different n_RFP values in the model. The dashed curve represents the dose response for the parameterized model based on experimental data. The RFP_p steady-states for each interaction channel length (colored marker styles) were computed for ara = 10. Inset: relationship between distance and steady-state RFP_p concentration for a range of n_RFP values. f Heatmap of distance sensitivity across a broad range of total LuxR concentrations (LuxR_tot) and binding affinities of the activated LuxR complex to the RFP_p promoter (K_RFP). Distance sensitivity is defined as the ratio of steady-state RFP_p concentration in a 25–250 μm condition. Source data are provided as a Source Data file.