Open AccessReengineering Escherichia coli for Succinate Production in Mineral Salts Medium
Author(s) -
X. Zhang,
Kaemwich Jantama,
K. T. Shanmugam,
L. O. Ingram
Publication year - 2009
Publication title -
applied and environmental microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.552
H-Index - 324
eISSN - 1070-6291
pISSN - 0099-2240
DOI - 10.1128/aem.01758-09
Subject(s) - phosphoenolpyruvate carboxykinase , phosphoenolpyruvate carboxylase , escherichia coli , biochemistry , fermentation , pep group translocation , metabolic engineering , succinic acid , biology , metabolic pathway , formate , chemistry , enzyme , gene , catalysis
The fermentative metabolism of glucose was redirected to succinate as the primary product without mutating any genes encoding the native mixed-acid fermentation pathway or redox reactions. Two changes in peripheral pathways were together found to increase succinate yield fivefold: (i) increased expression of phosphoenolpyruvate carboxykinase and (ii) inactivation of the glucose phosphoenolpyruvate-dependent phosphotransferase system. These two changes increased net ATP production, increased the pool of phosphoenolpyruvate available for carboxylation, and increased succinate production. Modest further improvements in succinate yield were made by inactivating thepflB gene, encoding pyruvate formate lyase, resulting in anE scherichia coli pathway that is functionally similar to the native pathway inActinobacillus succinogenes and other succinate-producing rumen bacteria.