Fig. 1

Theoretical stoichiometric comparison of the anaerobic metabolism of S. cerevisiae expressing a strictly NAD⁺-dependent 6-PGDH to wild-type S. cerevisiae. Numbers in boxes represent the carbon distribution and grey numbers in boxes represent the requirement for glucose and cofactors in mmol g ⁻¹_x , normalized for the formation of 1 g of biomass in the two scenarios: native, NADP⁺-dependent 6-PGDH (top, blue colour) and heterologous, NAD⁺-dependent 6-PGDH (bottom, red colour). Blue glycolysis and alcoholic fermentation; Green pentose-phosphate pathway; Purple glycerol formation pathway; Grey biosynthesis according to [68], which, together with the ATP requirement for biosynthesis, was assumed to be identical for both scenarios. The oxidative branch of the pentose phosphate pathway was assumed to be the only NADPH formation pathway. Figure adapted from [21]