Metabolic network model of the central carbon metabolism of S. cerevisiae. Metabolic network model of the central carbon metabolism of S. cerevisiae was applied in the 13C-metabolic flux analysis for determination of net fluxes in different oxygenation conditions. The cytosolic and mitochondrial compartments and glycolytic, pentose phosphate, TCA cycle and fermentative pathways were included in the model. The fluxes are presented as net fluxes and the directions of the arrows represent the directions of positive net fluxes. The compounds consumed or produced by external fluxes are denoted with a subscript ext. The anabolic reactions from metabolic intermediates to biosynthesis are represented by small arrows.