[Metabolic shift of Corynebacterium acetoacidophilum-deltaldh under oxygen deprivation conditions]

Sheng Wu Gong Cheng Xue Bao. 2014 Mar;30(3):435-44.
[Article in Chinese]

Abstract

Lactate and succinate were produced by Corynebacterium acetoacidophilum from glucose under oxygen deprivation conditions. To construct knockout mutant, lactate dehydrogenase gene (ldh) of C. acetoacidophilum was deleted by double-crossover chromosome replacement with sacB gene. Comparing with the wild strain ATCC13870, ldhA-deficent mutant produced no lactate with glucose consumption rate decreased by 29.3%, while succinate and acetate concentrations were increased by 45.6% and 182%, respectively. Moreover, the NADH/NAD+ rate was less than 1 (about 0.7), and the activities of phosphoenolpyruvate carboxylase and acetate kinase of the ldhA-deficent mutant were enhanced by 84% and 12 times, respectively. Our studies show that succinicate and acetate production pathways are strengthened by blocking lactate synthesis. It also suggests that improving NADH supply and eliminating acetate generation are alternative strategies to get high succinate-producer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Corynebacterium glutamicum / genetics
  • Corynebacterium glutamicum / metabolism*
  • Glucose
  • Industrial Microbiology
  • L-Lactate Dehydrogenase / genetics
  • L-Lactate Dehydrogenase / metabolism*
  • Lactic Acid / metabolism*
  • Oxygen / metabolism*
  • Phosphoenolpyruvate Carboxylase
  • Succinic Acid / metabolism*

Substances

  • Lactic Acid
  • Succinic Acid
  • L-Lactate Dehydrogenase
  • Phosphoenolpyruvate Carboxylase
  • Glucose
  • Oxygen