Team:British Columbia/modeling description

We developed a mathematical model that describes the dynamics of the biofilm structure (in terms of bacterial population size) and the interactions amongst the components, including the engineered phage and AIP. We used numerical simulations to predict the impact of phage and DspB release on the biofilm structure. We also investigated the weight of each parameter to the design of our system with sensitivity analysis. Possible scenarios of biofilm degradation suggested by our model are investigated.

The biofilm system assumes a simple planar geometry characterized by depth, D, and cross-sectional area, A (Figure 1). The density and distribution of the biofilm bacterial population, extracellular polymeric substance (EPS), and dissolved components (e.g. AIP and metabolites) are uniform throughout the biofilm structure. Assuming that each biofilm bacterium occupies a spherical volume of diameter, d, and the surrounding EPS extends this volume by a constant, Α, each bacterium takes up a cubic volume of (Α + d)^3.