Comparing the xylose reductase/xylitol dehydrogenase and xylose isomerase pathways in arabinose and xylose fermenting <it>Saccharomyces cerevisiae </it>strains
<p>Abstract</p> <p>Background</p> <p>Ethanolic fermentation of lignocellulosic biomass is a sustainable option for the production of bioethanol. This process would greatly benefit from recombinant <it>Saccharomyces cerevisiae </it>strains also able to fermen...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
BMC
2008-10-01
|
| Series: | Biotechnology for Biofuels |
| Online Access: | http://www.biotechnologyforbiofuels.com/content/1/1/16 |
| _version_ | 1811246313560342528 |
|---|---|
| author | Hahn-Hägerdal Bärbel Bettiga Maurizio Gorwa-Grauslund Marie F |
| author_facet | Hahn-Hägerdal Bärbel Bettiga Maurizio Gorwa-Grauslund Marie F |
| author_sort | Hahn-Hägerdal Bärbel |
| collection | DOAJ |
| description | <p>Abstract</p> <p>Background</p> <p>Ethanolic fermentation of lignocellulosic biomass is a sustainable option for the production of bioethanol. This process would greatly benefit from recombinant <it>Saccharomyces cerevisiae </it>strains also able to ferment, besides the hexose sugar fraction, the pentose sugars, arabinose and xylose. Different pathways can be introduced in <it>S. cerevisiae </it>to provide arabinose and xylose utilisation. In this study, the bacterial arabinose isomerase pathway was combined with two different xylose utilisation pathways: the xylose reductase/xylitol dehydrogenase and xylose isomerase pathways, respectively, in genetically identical strains. The strains were compared with respect to aerobic growth in arabinose and xylose batch culture and in anaerobic batch fermentation of a mixture of glucose, arabinose and xylose.</p> <p>Results</p> <p>The specific aerobic arabinose growth rate was identical, 0.03 h<sup>-1</sup>, for the xylose reductase/xylitol dehydrogenase and xylose isomerase strain. The xylose reductase/xylitol dehydrogenase strain displayed higher aerobic growth rate on xylose, 0.14 h<sup>-1</sup>, and higher specific xylose consumption rate in anaerobic batch fermentation, 0.09 g (g cells)<sup>-1 </sup>h<sup>-1 </sup>than the xylose isomerase strain, which only reached 0.03 h<sup>-1 </sup>and 0.02 g (g cells)<sup>-1</sup>h<sup>-1</sup>, respectively. Whereas the xylose reductase/xylitol dehydrogenase strain produced higher ethanol yield on total sugars, 0.23 g g<sup>-1 </sup>compared with 0.18 g g<sup>-1 </sup>for the xylose isomerase strain, the xylose isomerase strain achieved higher ethanol yield on consumed sugars, 0.41 g g<sup>-1 </sup>compared with 0.32 g g<sup>-1 </sup>for the xylose reductase/xylitol dehydrogenase strain. Anaerobic fermentation of a mixture of glucose, arabinose and xylose resulted in higher final ethanol concentration, 14.7 g l<sup>-1 </sup>for the xylose reductase/xylitol dehydrogenase strain compared with 11.8 g l<sup>-1 </sup>for the xylose isomerase strain, and in higher specific ethanol productivity, 0.024 g (g cells)<sup>-1 </sup>h<sup>-1 </sup>compared with 0.01 g (g cells)<sup>-1 </sup>h<sup>-1 </sup>for the xylose reductase/xylitol dehydrogenase strain and the xylose isomerase strain, respectively.</p> <p>Conclusion</p> <p>The combination of the xylose reductase/xylitol dehydrogenase pathway and the bacterial arabinose isomerase pathway resulted in both higher pentose sugar uptake and higher overall ethanol production than the combination of the xylose isomerase pathway and the bacterial arabinose isomerase pathway. Moreover, the flux through the bacterial arabinose pathway did not increase when combined with the xylose isomerase pathway. This suggests that the low activity of the bacterial arabinose pathway cannot be ascribed to arabitol formation via the xylose reductase enzyme.</p> |
| first_indexed | 2024-04-12T14:51:40Z |
| format | Article |
| id | doaj.art-6310b8c7bfa74fe7a91062d4fdb8b4ec |
| institution | Directory Open Access Journal |
| issn | 1754-6834 |
| language | English |
| last_indexed | 2024-04-12T14:51:40Z |
| publishDate | 2008-10-01 |
| publisher | BMC |
| record_format | Article |
| series | Biotechnology for Biofuels |
| spelling | doaj.art-6310b8c7bfa74fe7a91062d4fdb8b4ec2022-12-22T03:28:25ZengBMCBiotechnology for Biofuels1754-68342008-10-01111610.1186/1754-6834-1-16Comparing the xylose reductase/xylitol dehydrogenase and xylose isomerase pathways in arabinose and xylose fermenting <it>Saccharomyces cerevisiae </it>strainsHahn-Hägerdal BärbelBettiga MaurizioGorwa-Grauslund Marie F<p>Abstract</p> <p>Background</p> <p>Ethanolic fermentation of lignocellulosic biomass is a sustainable option for the production of bioethanol. This process would greatly benefit from recombinant <it>Saccharomyces cerevisiae </it>strains also able to ferment, besides the hexose sugar fraction, the pentose sugars, arabinose and xylose. Different pathways can be introduced in <it>S. cerevisiae </it>to provide arabinose and xylose utilisation. In this study, the bacterial arabinose isomerase pathway was combined with two different xylose utilisation pathways: the xylose reductase/xylitol dehydrogenase and xylose isomerase pathways, respectively, in genetically identical strains. The strains were compared with respect to aerobic growth in arabinose and xylose batch culture and in anaerobic batch fermentation of a mixture of glucose, arabinose and xylose.</p> <p>Results</p> <p>The specific aerobic arabinose growth rate was identical, 0.03 h<sup>-1</sup>, for the xylose reductase/xylitol dehydrogenase and xylose isomerase strain. The xylose reductase/xylitol dehydrogenase strain displayed higher aerobic growth rate on xylose, 0.14 h<sup>-1</sup>, and higher specific xylose consumption rate in anaerobic batch fermentation, 0.09 g (g cells)<sup>-1 </sup>h<sup>-1 </sup>than the xylose isomerase strain, which only reached 0.03 h<sup>-1 </sup>and 0.02 g (g cells)<sup>-1</sup>h<sup>-1</sup>, respectively. Whereas the xylose reductase/xylitol dehydrogenase strain produced higher ethanol yield on total sugars, 0.23 g g<sup>-1 </sup>compared with 0.18 g g<sup>-1 </sup>for the xylose isomerase strain, the xylose isomerase strain achieved higher ethanol yield on consumed sugars, 0.41 g g<sup>-1 </sup>compared with 0.32 g g<sup>-1 </sup>for the xylose reductase/xylitol dehydrogenase strain. Anaerobic fermentation of a mixture of glucose, arabinose and xylose resulted in higher final ethanol concentration, 14.7 g l<sup>-1 </sup>for the xylose reductase/xylitol dehydrogenase strain compared with 11.8 g l<sup>-1 </sup>for the xylose isomerase strain, and in higher specific ethanol productivity, 0.024 g (g cells)<sup>-1 </sup>h<sup>-1 </sup>compared with 0.01 g (g cells)<sup>-1 </sup>h<sup>-1 </sup>for the xylose reductase/xylitol dehydrogenase strain and the xylose isomerase strain, respectively.</p> <p>Conclusion</p> <p>The combination of the xylose reductase/xylitol dehydrogenase pathway and the bacterial arabinose isomerase pathway resulted in both higher pentose sugar uptake and higher overall ethanol production than the combination of the xylose isomerase pathway and the bacterial arabinose isomerase pathway. Moreover, the flux through the bacterial arabinose pathway did not increase when combined with the xylose isomerase pathway. This suggests that the low activity of the bacterial arabinose pathway cannot be ascribed to arabitol formation via the xylose reductase enzyme.</p>http://www.biotechnologyforbiofuels.com/content/1/1/16 |
| spellingShingle | Hahn-Hägerdal Bärbel Bettiga Maurizio Gorwa-Grauslund Marie F Comparing the xylose reductase/xylitol dehydrogenase and xylose isomerase pathways in arabinose and xylose fermenting <it>Saccharomyces cerevisiae </it>strains Biotechnology for Biofuels |
| title | Comparing the xylose reductase/xylitol dehydrogenase and xylose isomerase pathways in arabinose and xylose fermenting <it>Saccharomyces cerevisiae </it>strains |
| title_full | Comparing the xylose reductase/xylitol dehydrogenase and xylose isomerase pathways in arabinose and xylose fermenting <it>Saccharomyces cerevisiae </it>strains |
| title_fullStr | Comparing the xylose reductase/xylitol dehydrogenase and xylose isomerase pathways in arabinose and xylose fermenting <it>Saccharomyces cerevisiae </it>strains |
| title_full_unstemmed | Comparing the xylose reductase/xylitol dehydrogenase and xylose isomerase pathways in arabinose and xylose fermenting <it>Saccharomyces cerevisiae </it>strains |
| title_short | Comparing the xylose reductase/xylitol dehydrogenase and xylose isomerase pathways in arabinose and xylose fermenting <it>Saccharomyces cerevisiae </it>strains |
| title_sort | comparing the xylose reductase xylitol dehydrogenase and xylose isomerase pathways in arabinose and xylose fermenting it saccharomyces cerevisiae it strains |
| url | http://www.biotechnologyforbiofuels.com/content/1/1/16 |
| work_keys_str_mv | AT hahnhagerdalbarbel comparingthexylosereductasexylitoldehydrogenaseandxyloseisomerasepathwaysinarabinoseandxylosefermentingitsaccharomycescerevisiaeitstrains AT bettigamaurizio comparingthexylosereductasexylitoldehydrogenaseandxyloseisomerasepathwaysinarabinoseandxylosefermentingitsaccharomycescerevisiaeitstrains AT gorwagrauslundmarief comparingthexylosereductasexylitoldehydrogenaseandxyloseisomerasepathwaysinarabinoseandxylosefermentingitsaccharomycescerevisiaeitstrains |