Figure 5.

Simulated predictions resulting from flux balance analysis were mapped onto reactions belonging to the Calvin-Benson cycle and photosynthetic reactions for mixotrophic growth. Absolute fluxes (mmol gdw⁻¹ h⁻¹) were categorized as low (<5 mmol gdw⁻¹ h⁻¹, thin blue arrow), medium, (>5–10 mmol gdw⁻¹ h⁻¹, red arrow) and high (>10 mmol gdw⁻¹ h⁻¹, thickest black arrows). The simulations revealed an input of flux from the pentose phosphate pathway into the Calvin-Benson cycle, and flux being diverted away from CO₂ and into ribulose 5-phosphate. Calvin-Benson cycle fluxes were further maintained by triose phosphate entry into the cycle, originating from within the mitochondrion. Upon inspection of photosynthetic fluxes, a cycling of electrons around photosystem I into the plastoquinone pool was active, resulting in flux diversion from the production of NAPDH back into the electron transport chain at plastoquinone. As a result of electron re-direction, ATP production is increased. 1,3DPG, 3-Phospho-D-glyceroyl phosphate; 3PG, 3-Phospho-D-glycerate; 6PGC, 6-Phospho-Gluconate; ATPase, ATP synthase; ATPSH, ATP producing synthase; b6f, Cytochrome b6F; CEF, Cyclic Electron Flow; DHAP, Dihydroxyacetone phosphate; DM_o2D(u), Oxygen Demand; E4P, Erythrose 4-phosphate; F6P, Fructose 6-phosphate; FBA3hi, Sedoheptulose 1,7-bisphosphate D-glyceraldehyde-3-phosphate-lyase; FD, Feredoxin; FDP, Fructose 1,6-bisphosphate; FNORh, Ferredoxin-NADP+ Reductase; G3P, Glyceraldehyde 3-phosphate; GAPDHh, Glyceraldehyde 3-phosphate dehydrogenase; OPPP, Oxidative Pentose Phosphate Pathway; PC, Plastocyanin; PGDHh, 6-Phosphogluconate Dehydrogenase; PGKh, Phosphoglycerate kinase; PQ, Plastoquinone; PSI, Photosystem I; PSII, Photosystem II; R5P, Ribose 5-phosphate; RB15BP, Ribulose 1,5-bisphosphate; RPEh, Ribulose-5-Phosphate; RPIh, Ribose-5-phosphate isomerase; Ru5P, Ribulose 5-phosphate, 3-Epimerase; S17BP, Sedoheptulose 1,7-bisphosphate; S7P, Sedoheptulose 7-phosphate; TKT1h, transketolase 1; TPIh, triose phosphate isomerase; Xu5P, Xylulose 5-phosphate.