(A) Predicted cell-specific net metabolite uptake rates in coculture. (B) Predicted cell-specific reaction rates in coculture, for acs (acetyl-CoA synthesis), ack (acetate synthesis), pta (acetyl phosphate synthesis), ppc (oxaloacetate synthesis from phosphoenolpyruvate), pdh (decarboxylation of pyruvate to acetyl-CoA) and pyk (pyruvate synthesis from phosphoenolpyruvate). Rates in (A) and (B) are averaged over all time points within the first 100 days of evolution, with reversed reactions or net metabolite export represented by negative rates. (C) and (D): Simplified model subset of E. coli acetate and glucose metabolism, showing pathway activations in type SS (C) and FS (D) relative to type A during exponential growth in monoculture. Non-bracketed numeric values are ratios of predicted fluxes in the evolved types over fluxes in type A. Bracketed values are ratios of mRNA harvested from monoculture experiments by Le Gac et al. (2008), for comparison. A ratio of 0/0 indicates zero flux in both the evolved and ancestral type, a ratio of 1 corresponds to an unchanged flux or mRNA, a ratio of 0 corresponds to complete deactivation in the evolved type. Darker arrows indicate increased predicted fluxes in the evolved type. Flux predictions correspond to the time points of mRNA measurements, that is, 3.5 hr after dilution for SS and 4 hr after dilution for A and SS (Le Gac et al., 2008).