@bastian

L-valine production with pyruvate dehydrogenase complex-deficient Corynebacterium glutamicum

, , , , , und . Appl. Environ. Microbiol. 73 (7): 2079--2084 (April 2007)

Zusammenfassung

Corynebacterium glutamicum was engineered for the production of L-valine from glucose by deletion of the aceE gene encoding the E1p enzyme of the pyruvate dehydrogenase complex and additional overexpression of the ilvBNCE genes encoding the L-valine biosynthetic enzymes acetohydroxyacid synthase, isomeroreductase, and transaminase B. In the absence of cellular growth, C. glutamicum DeltaaceE showed a relatively high intracellular concentration of pyruvate (25.9 mM) and produced significant amounts of pyruvate, L-alanine, and L-valine from glucose as the sole carbon source. Lactate or acetate was not formed. Plasmid-bound overexpression of ilvBNCE in C. glutamicum DeltaaceE resulted in an approximately 10-fold-lower intracellular pyruvate concentration (2.3 mM) and a shift of the extracellular product pattern from pyruvate and L-alanine towards L-valine. In fed-batch fermentations at high cell densities and an excess of glucose, C. glutamicum DeltaaceE(pJC4ilvBNCE) produced up to 210 mM L-valine with a volumetric productivity of 10.0 mM h(-1) (1.17 g l(-1) h(-1)) and a maximum yield of about 0.6 mol per mol (0.4 g per g) of glucose.

Links und Ressourcen

DOI:
10.1128/AEM.02826-06
BibTeX-Schlüssel:
blombach_l-valine_2007
Suchen auf:

Kommentare und Rezensionen  
(0)

Es gibt bisher keine Rezension oder Kommentar. Sie können eine schreiben!

Tags


Zitieren Sie diese Publikation