Improved ethanol productivity from lignocellulosic hydrolysates by Escherichia coli with regulated glucose utilization
Date
2018-05-02
Journal Title
Journal ISSN
Volume Title
Publisher
BioMed Central
Abstract
Background: Lignocellulosic ethanol could offer a sustainable source to meet the increasing worldwide demand for
fuel. However, efficient and simultaneous metabolism of all types of sugars in lignocellulosic hydrolysates by ethanolproducing
strains is still a challenge.
Results: An engineered strain Escherichia coli B0013-2021HPA with regulated glucose utilization, which could use all
monosaccharides in lignocellulosic hydrolysates except glucose for cell growth and glucose for ethanol production,
was constructed. In E. coli B0013-2021HPA, pta-ackA, ldhA and pflB were deleted to block the formation of acetate,
lactate and formate and additional three mutations at glk, ptsG and manZ generated to block the glucose uptake and
catabolism, followed by the replacement of the wild-type frdA locus with the ptsG expression cassette under the control
of the temperature-inducible λ pR and pL promoters, and the final introduction of pEtac-PA carrying Zymomonas
mobilis pdc and adhB for the ethanol pathway. B0013-2021HPA was able to utilize almost all xylose, galactose and
arabinose but not glucose for cell propagation at 34 °C and converted all sugars to ethanol at 42 °C under oxygenlimited
fermentation conditions.
Conclusions: Engineered E. coli strain with regulated glucose utilization showed efficient metabolism of mixed sugars
in lignocellulosic hydrolysates and thus higher productivity of ethanol production.
Description
CITATION: Sun, Jinfeng, et al. 2018. Improved ethanol productivity from lignocellulosic hydrolysates by Escherichia coli with regulated glucose utilization. Microbial Cell Factories, 17:66, doi:10.1186/s12934-018-0915-x.
The original publication is available at https://microbialcellfactories.biomedcentral.com
The original publication is available at https://microbialcellfactories.biomedcentral.com
Keywords
Ethanol production, Lignocellulosic hydrolysate, Escherichia coli, Glucose utilization
Citation
Sun, Jinfeng, et al. 2018. Improved ethanol productivity from lignocellulosic hydrolysates by Escherichia coli with regulated glucose utilization. Microbial Cell Factories, 17:66, doi:10.1186/s12934-018-0915-x