fig6

Figure 6. (A) Methanotrophs initially consume both nitrate (from the culture medium) and ammonium (produced by cyanobacteria), but consume only ammonium produced by A. platensis after ~45 h. This dynamic evolution coincides with the significant increase in glutamate exchange (Glu-M and Glu-C) within coculture, as shown in (B). Positive values indicate production while negative values indicate consumption. The irregularities (i.e., the non-smooth parts) in the prediction are the consequence of the change of CH₄/CO₂ uptake by the species during and after refeeding the system.