Journal
BIOPROCESS AND BIOSYSTEMS ENGINEERING
Volume 33, Issue 7, Pages 873-883Publisher
SPRINGER
DOI: 10.1007/s00449-010-0410-1
Keywords
Corynebacterium glutamicum; L-Valine; Pyruvate dehydrogenase complex; Substrate uptake; Fermentation process development; Xylulose
Funding
- BMVEL-Federal Ministry of Food, Agriculture and Consumer Protection [04NR003/22000304]
- Evonik Degussa GmbH
Ask authors/readers for more resources
The pyruvate dehydrogenase complex was deleted to increase precursor availability in Corynebacterium glutamicum strains overproducing l-valine. The resulting auxotrophy is treated by adding acetate in addition glucose for growth, resulting in the puzzling fact of gluconeogenic growth with strongly reduced glucose uptake in the presence of acetate in the medium. This result was proven by intracellular metabolite analysis and labelling experiments. To increase productivity, the SugR protein involved in negative regulation of the phosphotransferase system, was inactivated, resulting in enhanced consumption of glucose. However, the surplus in substrate uptake was not converted to l-valine; instead, the formation of up to 289 mu M xylulose was observed for the first time in C. glutamicum. As an alternative to the genetic engineering solution, a straightforward process engineering approach is proposed. Acetate limitation resulted in a more efficient use of acetate as cosubstrate, shown by an increased biomass yield Y (X/Ac) and improved l-valine formation.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available