Table 1.
Extracted fluxes using bonded cumomer modeling.
| Reaction | Flux (mmol/L-cell/h)a |
|---|---|
| Pentose phosphate pathway (oxidative branch), net PPP FpppOx | 3.3 ± 72% |
| Transketolase 1 (exchange) relative to glycolysis, TK1 | 21 ± 56% |
| Transketolase 2 (exchange) relative to glycolysis, TK2 | 0.5 ± 90% |
| Transaldolase (exchange) relative to glycolysis, TA | 44 ± 64% |
| Glucogenic amino acids contribution to pyruvate, Fgaa | 5.0 ± 20% |
| TCA cycle rate, Ftca (isocitrate → α-Kg) | 10.9 ± 8% |
| Exchange, Mal-Asp shuttle, Fx (reversible) | 11.3 ± 19% |
| Pyruvate carboxylase Flux, Fpc | 0.6 ± 51% |
| Anaplerotic exchange flux at SucCoA, Fxana | 3.0 ± 15% |
| Net Anaplerotic flux to the TCA cycle, dFana | 4.3 ± 15% |
| Flux of ketogenic AA and FA to Acetyl-CoA formation, Fkaa | 0.1 ± 19% |
| Glutaminolysis Flux, Fgls | 0.05 ± 60% |
| Pyruvate dehydrogenase Flux, Fpdh | 10.8 ± 16% |
| Citrate synthase flux, Fcs | 11.5 ± 14% |
| Net fumarase activity, Fum →Mal, Ffum | 15.3 ± 16% |
| Fatty acids synthesis, Ffas | 0.59 ± 15% |
| Mitochondrial pyruvate transport, Fmpc | 7.1 ± 23% |
| Malic enzyme (mitochondrion), ME2 + ME3, Fmem | 4.3 ± 12% |
| Malic enzyme (cytosolic), ME1, Fmec | 0.6 ± 15% |
| Aspartate efflux, dFxasp | 0.06 ± 45% |
| Production Flux of ATP, glycolytic, Warburg, FatpCyt | 150 ± 13% |
| Production Flux of ATP, mitochondrial, oxphos, FatpOx | 154 ± 12% |
| Warburg parameter (net LDH/MPC flux ratio) | 21 ± 24% (unitless) |
| Combined glycolysis and PPP flux from G6P to pyruvate | 152.1 ± 12% |
| Glutamine consumption flux (for protein, nucleotides, amino acids, glutathione, etc) | 4.9 ± 10%b |
| Net LDH activity, Pyr → Lac, Fldh | 150 ± 12% |
| Lactate transport, Vmaxlac | 395 ± 12% |
| Lactate transport, Michaelis–Menten parameter, Km | 3.5 mM ± 70% |
aCalculated rates of flux are expressed in millimoles per liter-cell per hour with relative SDs in percent for pathways shown in Figure 1. Warburg parameter is the ratio of the net flux through lactate dehydrogenase (LDH) to the mitochondrial pyruvate carrier influx (MPC).
bSD was estimated based on experimental measurements of glutamine consumption.
This research was originally published in Journal of Biological Chemistry. Shestov et al. (14). © the American Society for Biochemistry and Molecular Biology.