A computational knowledge-base elucidates the response of Staphylococcus aureus to different media types
Fig 5
Comparison of flux distribution across two condition-specific GEMs.
(A) The reactions that were shown to significantly differ in their flux distribution (determined by the Kolmogorov-Smirnoff test) between the CDMG- and CDM-specific GEM are shown. The width of the arrows qualitatively represents the median flux value across 10,000 sampled fluxes. The blue arrows represent the flux simulation results for the CDM-specific GEM and the red arrows represent the flux simulations of the CDMG-specific GEM. The13C labelled intracellular metabolites detected by NMR in both conditions are highlighted in red (metabolic intermediates derived from extracellular glucose in CDMG) and in blue (metabolic intermediates derived from nine extracellular amino acids in CDM) [79]. Metabolites highlighted in grey are present in the extracellular medium (note that D-glucose is only present in CDMG). (B) Differential cycling of ammonium (as well as several cofactors) between the two GEMs highlights the relative contribution to the production and consumption of ammonium for all reactions utilizing or synthesizing ammonium in CDM (blue) and CDMG (red). Several metabolic processes contribute to the ammonium pool in CDM (including the glycine cleavage system) while serine dehydrogenase is the main source of ammonium in CDMG.