Flux balance analysis of the ammonia-oxidizing bacterium Nitrosomonas europaea ATCC19718 unravels specific metabolic activities while degrading toxic compounds
Fig 2
Map of the metabolic flux distributions predicted under chemolithoorganotrophic and chemolithotrophic conditions.
The map shows the changes in the flux distributions under four different growth conditions. Ammonium is present under all conditions but changing the carbon source (fructose, pyruvate, and HCO3-). (A) Chemolithoorganotrophy metabolism. The fructose uptake rate was constrained to 0.746 mmol/gDW/h, and the ammonium uptake rate was 0.5mmol/gDW/h. (B) Chemolithotrophy metabolism. HCO3- uptake rates were constrained to 4.35 mmol/gDW/h for high and 1.43 mmol/gDW/h for low. Abbreviations: HCO3E, carbonic anhydrase; PYK, pyruvate kinase; PPS, phosphoenolpyruvate synthasePGK, phosphoglycerate kinase; GAPD, glyceraldehyde 3-phosphate dehydrogenase; PFK, phosphofructokinase; PGI, glucose 6-phosphate isomerase; G6PDH2r, glucose 6-phosphate dehydrogenase; PGL, 6-phosphogluconolactonase; GND, phosphogluconate dehydrogenase; RPI, ribose-5-phosphate isomerase; RPE, ribulose 5-phosphate 3-epimerase; TKT, transketolase; TPI, triose-phosphate isomerase; PRUK, phosphoribulokinase; RBPC, ribulose 1,5-bisphosphate carboxylase-oxygenase; PDH, pyruvate dehydrogenase; CS, citrate synthase; MDH, malate dehydrogenase; SUCDi, succinate dehydrogenase; SUCOAS, succinyl-CoA synthetase; AKGDH, 2-oxoglutarate dehydrogenase; ICDHyr, isocitrate dehydrogenase; ORNTAC, ornithine transacetylase; G6P, D-Glucose 6-phosphate; F6P, D-Fructose 6-phosphate; FDP, D-Fructose 1,6-bisphosphate; G3P, Glyceraldehyde 3-phosphate; 13DPG, 3-Phospho-D-glyceroyl phosphate; 3PG, 3-Phospho-D-glycerate; 2PG, D-Glycerate 2-phosphate; PEP, Phosphoenolpyruvate; Pyr, Pyruvate; AcCoA, Acetyl-CoA; Fru, D-Fructose; Cit, citrate; Acon, Aconitate; iCit, Isocitrate; AKG, 2-Oxoglutarate; SucCoA, Succinyl-CoA; Suc, Succinate; Fum, Fumarate; Mal, L-Malate; OAA,Oxaloacetate; ArgSuc, L-Argininosuccinate; L-Citr, L-Citrulline; Orn, Ornithine; AcOrn, Acetylornithine; AcGlu, Acetyl-L-glutamate; AcG5P, Acetyl-L-glutamate 5-phosphate; AcG5SA, Acetyl-L-glutamate 5-semialdehyde; L-Glu, L-Glutamate; RuBP, D-Ribose 1,5-bisphosphate; Ru5P, D-Ribulose 5-phosphate; Xu5P, D-Xylulose 5-phosphate; DHAP, Dihydroxyacetone phosphate; E4P, Erythrose 4-phosphate dehydrogenase; S7P, Sedoheptulose 7-phosphate; S17BP, Sedoheptulose 1,7-bisphosphate; R5P, Ribose 5-phosphate; 6PGC, 6-Phospho-D-gluconate; 6PGL, 6-phospho-D-glucono-1,5-lactone.