Fig. 6
A, B Visualization of metabolic exchanges occurring between the most abundant species present in the biofilm and/or the medium. The purple circle represents the medium and grey circles the most abundant MAGs. The circle diameter is proportional to the microbe average relative abundance in the four biofilm samples. Results for key compounds related to biogas upgrading process (A) and all exchanged amino acids (B) are reported. Arrows thickness is proportional to the fluxes between species. C Effects of changes operated on feedstock and microbes’ abundance on amino acids, H2, CO2, and CH4 production. Targeted intervention on feedstock components or microbe species are in columns and the influenced export reactions in rows. Colors refer to elasticity, which is the change in metabolites production determined by an increase in the specific effector. Red/blue colors denote changes that would respectively increase/decrease the metabolite production. Only targeted intervention with nonzero elasticity for at least one of the selected compounds are reported. The types of intervention tested are divided in shifts of metabolites availability in green and species abundance in blue