Journal
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
Volume 97, Issue 6, Pages 2597-2607Publisher
SPRINGER
DOI: 10.1007/s00253-012-4376-6
Keywords
Ethanol; Xylose fermentation; Furfural; 5-Hydroxymethylfurfural; Redox imbalance; Saccharomyces cerevisiae
Categories
Funding
- New Energy and Industrial Technology Development Organization (NEDO) under Ministry of Economy, Trade, and Industry (METI) of Japan [P07015]
- Global Warming Countermeasure Technology Development Program from the Ministry of the Environment of Japan
- Ministry of Education, Culture, Sports and Technology (MEXT) of Japan
- Special Coordination Fund for Promoting Science and Technology, Creation of Innovative Centers for Advanced Interdisciplinary Research Areas (Innovative Bioproduction Kobe) from MEXT, Japan
Ask authors/readers for more resources
Several alcohol dehydrogenase (ADH)-related genes have been identified as enzymes for reducing levels of toxic compounds, such as, furfural and/or 5-hydroxymethylfurfural (5-HMF), in hydrolysates of pretreated lignocelluloses. To date, overexpression of these ADH genes in yeast cells have aided ethanol production from glucose or glucose/xylose mixture in the presence of furfural or 5-HMF. However, the effects of these ADH isozymes on ethanol production from xylose as a sole carbon source remain uncertain. We showed that overexpression of mutant NADH-dependent ADH1 derived from TMB3000 strain in the recombinant Saccharomyces cerevisiae, into which xylose reductase (XR) and xylitol dehydrogenase (XDH) pathway of Pichia stipitis has been introduced, improved ethanol production from xylose as a sole carbon source in the presence of 5-HMF. Enhanced furan-reducing activity is able to regenerate NAD(+) to relieve redox imbalance, resulting in increased ethanol yield arising from decreased xylitol accumulation. In addition, we found that overexpression of wild-type ADH1 prevented the more severe inhibitory effects of furfural in xylose fermentation as well as overexpression of TMB3000-derived mutant. After 120 h of fermentation, the recombinant strains overexpressing wild-type and mutant ADH1 completely consumed 50 g/L xylose in the presence of 40 mM furfural and most efficiently produced ethanol (15.70 g/L and 15.24 g/L) when compared with any other test conditions. This is the first report describing the improvement of ethanol production from xylose as the sole carbon source in the presence of furan derivatives with xylose-utilizing recombinant yeast strains via the overexpression of ADH-related genes.
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