%0 Journal Article %1 krause_metabolic_2010 %A Krause, Felix S. %A Blombach, Bastian %A Eikmanns, Bernhard J. %D 2010 %J Appl. Environ. Microbiol. %K Acids, Bacterial, Corynebacterium Deletion, Engineering, Expression, Gene Genes, Genetic Genetically Glucose, Keto Metabolic Modified Networks Organisms, Pathways, and glutamicum, myown %N 24 %P 8053--8061 %R 10.1128/AEM.01710-10 %T Metabolic engineering of Corynebacterium glutamicum for 2-ketoisovalerate production %V 76 %X 2-Ketoisovalerate is used as a therapeutic agent, and a 2-ketoisovalerate-producing organism may serve as a platform for products deriving from this 2-keto acid. We engineered the wild type of Corynebacterium glutamicum for the growth-decoupled production of 2-ketoisovalerate from glucose by deletion of the aceE gene encoding the E1p subunit of the pyruvate dehydrogenase complex, deletion of the transaminase B gene ilvE, and additional overexpression of the ilvBNCD genes, encoding the l-valine biosynthetic enzymes acetohydroxyacid synthase (AHAS), acetohydroxyacid isomeroreductase, and dihydroxyacid dehydratase. 2-Ketoisovalerate production was further improved by deletion of the pyruvate:quinone oxidoreductase gene pqo. In fed-batch fermentations at high cell densities, the newly constructed strains produced up to 188 ± 28 mM (21.8 ± 3.2 g liter(-1)) 2-ketoisovalerate and showed a product yield of about 0.47 ± 0.05 mol per mol (0.3 ± 0.03 g per g) of glucose and a volumetric productivity of about 4.6 ± 0.6 mM (0.53 ± 0.07 g liter(-1)) 2-ketoisovalerate per h in the overall production phase. In studying the influence of the three branched-chain 2-keto acids 2-ketoisovalerate, 2-ketoisocaproate, and 2-keto-3-methylvalerate on the AHAS activity, we observed a competitive inhibition of the AHAS enzyme by 2-ketoisovalerate.

@article{krause_metabolic_2010, abstract = {2-Ketoisovalerate is used as a therapeutic agent, and a 2-ketoisovalerate-producing organism may serve as a platform for products deriving from this 2-keto acid. We engineered the wild type of Corynebacterium glutamicum for the growth-decoupled production of 2-ketoisovalerate from glucose by deletion of the aceE gene encoding the E1p subunit of the pyruvate dehydrogenase complex, deletion of the transaminase B gene ilvE, and additional overexpression of the ilvBNCD genes, encoding the l-valine biosynthetic enzymes acetohydroxyacid synthase (AHAS), acetohydroxyacid isomeroreductase, and dihydroxyacid dehydratase. 2-Ketoisovalerate production was further improved by deletion of the pyruvate:quinone oxidoreductase gene pqo. In fed-batch fermentations at high cell densities, the newly constructed strains produced up to 188 ± 28 mM (21.8 ± 3.2 g liter(-1)) 2-ketoisovalerate and showed a product yield of about 0.47 ± 0.05 mol per mol (0.3 ± 0.03 g per g) of glucose and a volumetric productivity of about 4.6 ± 0.6 mM (0.53 ± 0.07 g liter(-1)) 2-ketoisovalerate per h in the overall production phase. In studying the influence of the three branched-chain 2-keto acids 2-ketoisovalerate, 2-ketoisocaproate, and 2-keto-3-methylvalerate on the AHAS activity, we observed a competitive inhibition of the AHAS enzyme by 2-ketoisovalerate.}, added-at = {2018-02-09T13:18:17.000+0100}, author = {Krause, Felix S. and Blombach, Bastian and Eikmanns, Bernhard J.}, biburl = {https://puma.ub.uni-stuttgart.de/bibtex/2bc1670b16ed84beabd8820d13e46b2d2/bastian}, doi = {10.1128/AEM.01710-10}, interhash = {3154880de1726a3496ebe8869a0a7468}, intrahash = {bc1670b16ed84beabd8820d13e46b2d2}, issn = {1098-5336}, journal = {Appl. Environ. Microbiol.}, keywords = {Acids, Bacterial, Corynebacterium Deletion, Engineering, Expression, Gene Genes, Genetic Genetically Glucose, Keto Metabolic Modified Networks Organisms, Pathways, and glutamicum, myown}, language = {eng}, month = dec, number = 24, pages = {8053--8061}, pmcid = {PMC3008247}, pmid = {20935122}, timestamp = {2018-02-09T12:18:56.000+0100}, title = {Metabolic engineering of {Corynebacterium} glutamicum for 2-ketoisovalerate production}, volume = 76, year = 2010 }