Supplementation of intracellular XylR leads to coutilization of hemicellulose sugars.
Appl Environ Microbiol
; 78(7): 2221-9, 2012 Apr.
Article
in En
| MEDLINE
| ID: mdl-22286982
ABSTRACT
Escherichia coli has the potential to be a powerful biocatalyst for the conversion of lignocellulosic biomass into useful materials such as biofuels and polymers. One important challenge in using E. coli for the transformation of biomass sugars is diauxie, or sequential utilization of different types of sugars. We demonstrate that, by increasing the intracellular levels of the transcription factor XylR, the preferential consumption of arabinose before xylose can be eliminated. In addition, XylR augmentation must be finely tuned for robust coutilization of these two hemicellulosic sugars. Using a novel technique for scarless gene insertion, an additional copy of xylR was inserted into the araBAD operon. The resulting strain was superior at cometabolizing mixtures of arabinose and xylose and was able to produce at least 36% more ethanol than wild-type strains. This strain is a useful starting point for the development of an E. coli biocatalyst that can simultaneously convert all biomass sugars.
Full text:
1
Database:
MEDLINE
Main subject:
Arabinose
/
Polysaccharides
/
Transcription Factors
/
Xylose
/
Biotechnology
/
Escherichia coli Proteins
/
Escherichia coli
Type of study:
Evaluation_studies
Language:
En
Journal:
Appl Environ Microbiol
Year:
2012
Type:
Article
Affiliation country:
United States