ATP-Based Ratio Regulation of Glucose and Xylose Improved Succinate Production
نویسندگان
چکیده
We previously engineered E. coli YL104H to efficiently produce succinate from glucose. Furthermore, the present study proved that YL104H could also co-utilize xylose and glucose for succinate production. However, anaerobic succinate accumulation using xylose as the sole carbon source failed, probably because of an insufficient supply of energy. By analyzing the ATP generation under anaerobic conditions in the presence of glucose or xylose, we indicated that succinate production was affected by the intracellular ATP level, which can be simply regulated by the substrate ratio of xylose to glucose. This finding was confirmed by succinate production using an artificial mixture containing different xylose to glucose ratios. Using xylose mother liquor, a waste containing both glucose and xylose derived from xylitol production, a final succinate titer of 61.66 g/L with an overall productivity of 0.95 g/L/h was achieved, indicating that the regulation of the intracellular ATP level may be a useful and efficient strategy for succinate production and can be extended to other anaerobic processes.
منابع مشابه
METABOLIC CAPABILITIES OF Actinobacillus succinogenes FOR SUCCINIC ACID PRODUCTION
Attention has been focused on microbial succinic acid production as an alternative for conventional chemical synthesis that is associated with environmental pollution. A metabolic model for Actinobacillus succinogenes 130Z was developed with a mixture of glucose and xylose as substrate. The metabolic fluxes during succinicate production were determined using flux balance analysis by linear prog...
متن کاملComparison of individual component deletions in a glucose-specific phosphotransferase system revealed their different applications
The phosphoenolpyruvate-dependent glucose-specific phosphotransferase system (PTS(Glc)) is the main glucose uptake pathway in Escherichia coli that affects both substrate assimilation and metabolism leading to the product formation. In this study, the effect of single PTS(Glc) mutation on cell growth and substrate consumption was investigated by knocking out the genes involved in the phosphotra...
متن کاملMolecular basis for anaerobic growth of Saccharomyces cerevisiae on xylose, investigated by global gene expression and metabolic flux analysis.
Yeast xylose metabolism is generally considered to be restricted to respirative conditions because the two-step oxidoreductase reactions from xylose to xylulose impose an anaerobic redox imbalance. We have recently developed, however, a Saccharomyces cerevisiae strain that is at present the only known yeast capable of anaerobic growth on xylose alone. Using transcriptome analysis of aerobic che...
متن کاملImpact of an energy-conserving strategy on succinate production under weak acidic and anaerobic conditions in Enterobacter aerogenes
BACKGROUND Succinate is an important C4 building block chemical, and its production via fermentative processes in bacteria has many practical applications in the biotechnology field. One of the major goals of optimizing the bacterium-based succinate production process is to lower the culture pH from the current neutral conditions, as this would reduce total production costs. In our previous stu...
متن کاملGenetic engineering for improved xylose fermentation by yeasts.
Xylose utilization is essential for the efficient conversion of lignocellulosic materials to fuels and chemicals. A few yeasts are known to ferment xylose directly to ethanol. However, the rates and yields need to be improved for commercialization. Xylose utilization is repressed by glucose which is usually present in lignocellulosic hydrolysates, so glucose regulation should be altered in orde...
متن کامل