Improved Succinate Production by Metabolic Engineering
Table 2
Comparison of maximum theoretical yield of each pathway in E. coli.
Means of culture
Means of glucose intake
Succinate production pathway
Maximum theoretical yield (mol mol−1)
PTS
The reductive branch of the TCA cycle
1
Anaerobic culture
Glucokinase
The reductive branch of the TCA cycle
1.33
PTS
The reductive branch of the TCA cycle and activated glyoxylate pathway
1.2
Glucokinase
The reductive branch of the TCA cycle and activated glyoxylate pathway
1.71
PTS
The oxidative TCA cycle with inactivation of sdhA gene
1
Aerobic culture
Glucokinase
The oxidative TCA cycle with inactivation of sdhA gene and activated glyoxylate pathway
1
PTS
The oxidative TCA cycle with inactivation of sdhA gene
1
Glucokinase
The oxidative TCA cycle with inactivation of sdhA gene and activated glyoxylate pathway
1
These theoretical yields in anaerobic culture were calculated assuming that NADH and NAD are balanced as a result of central carbon metabolism. These theoretical yields in aerobic culture were calculated assuming that oxygen is the H-acceptor.