• G. Huerta-Beristain
  • J. Utrilla-Carreri
  • G. Hernández-Chávez
  • F. Bolívar
  • G. Gosset
  • A. Martínez
Keywords: metabolic flux control, glycolytic flux, ethanol flux, pyruvate decarboxylase, xylose, and glucose


Modification of ethanol flux, using glucose or xylose as carbon source, in ethanologenic Escherichia coli KO11 was studied, by increasing the activity of key carbon metabolism enzymes. KO11 strain contains, integrated into the chromosome, genes that code for pyruvate decarboxylase (PdcZm) and alcohol dehydrogenase (AdhBZm) from Zymomonas mobilis. Results indicate that KO11 has limited Pdc activity to channel carbon flux to ethanol formation from glucose or xylose. Hence, flux control is outside glycolysis and Pdc controls the ethanol flux. When intracellular activity of Pdc was increased 6 fold, the theoretical yield of ethanol on glucose or xylose was increased by 27%, during the stationary phase the ethanol flux was increased 42 and 44%, and the organic acid formation rate was reduced 46 and 76% for glucose or xylose, respectively. Furthermore, as a response to allosteric effects and a limited Pdc activity, an increase in the phosphofructokinase or pyruvatekinase enzymatic activity drastically reduces glucose consumption and ethanol formation flux, with a concomitant increase in organic acid formation.


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How to Cite
Huerta-Beristain, G., Utrilla-Carreri, J., Hernández-Chávez, G., Bolívar, F., Gosset, G., & Martínez, A. (2020). METABOLIC ENGINEERING TO INCREASE THE ETHANOL FLUX AND YIELD IN ETHANOLOGENIC Escherichia coli. Revista Mexicana De Ingeniería Química, 4(1), 25-36. Retrieved from

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