where Mglc and Mace represent the biomass of the glucose-consuming and acetate-consuming cells, respectively, gglc and gace represent their growth rates, vglc and vace represent the uptake rates of glucose and acetate, respectively, and εace represents the acetate production rate by glucose-consumers. Because the experimental data includes growth curves for cultures growing in only glucose and only acetate, gglc and gace were easily fit assuming an exponential form (see Additional file 1: Figure S2 A). Using these values and the glucose and acetate concentration curves from the same single substrate experiments, values for vglc, vace, and εace were fit (see Additional file 1: Figure S2 B magenta and blue, C blue). Finally, with these values fixed, the switching rate parameters, {αi}, that appear in Equation 11 were fit.