To account for the change in the redox balance inKlebsiella transformants overexpressing PDOR, a decrease in lacticacid, acetic acid, and ethanol production was observed, frequentlyconcomitant with an increase in succinic acid and 2,3-butanediolproduction. In C. freundii, expression of heterologous PDOR trig-gered improved 1,3-PD production, accompanied by significantlyincreased lactic acid titer (in the flasks: 6.32–10.5 g/L, and in thebioreactors: 9.21–16.37 g/L). Fig. 7 illustrates the carbon flux dis-tribution between the particular metabolic pathways at 48 h of the