Succinic acid (succinate) and its derivatives have a wide range of applications in the food and chemical industries. Escherichia coli can sequester CO₂ through PEP carboxylase to convert PEP into oxaloacetate, and further into succinate. A readily available industrial source of CO₂ is flue gas from power plants which can contain several other gases such as NO₂, SO₂, CO and O₂. Two-phase fermentations (an aerobic growth phase followed by an anaerobic production phase) were conducted to produce succinate using E. coli AFP111, which contains mutations in pyruvate formate lyase (pfl), lactate dehydrogenase (ldhA) and the phosphotransferase system (ptsG). Gases normally found in flue gas (CO₂, NO₂, SO₂, CO, O₂) were studied. CO₂ concentration in gas phase affected succinate formation. Supplying 50-200 ppm NO₂ or 50-300 ppm SO₂ (commonly found in flue gas) during the anaerobic production phase did not deleteriously affect succinate production. The effect of other gas components (100-500 ppm CO or 1-10% O₂) on succinate production is also reported.