Increased Ethanol Productivity in Xylose-Utilizing Saccharomyces cerevisiae via a Randomly Mutagenized Xylose Reductase
(2010) In Applied and Environmental Microbiology 76(23). p.7796-7802- Abstract
- Baker's yeast (Saccharomyces cerevisiae) has been genetically engineered to ferment the pentose sugar xylose present in lignocellulose biomass. One of the reactions controlling the rate of xylose utilization is catalyzed by xylose reductase (XR). In particular, the cofactor specificity of XR is not optimized with respect to the downstream pathway, and the reaction rate is insufficient for high xylose utilization in S. cerevisiae. The current study describes a novel approach to improve XR for ethanol production in S. cerevisiae. The cofactor binding region of XR was mutated by error-prone PCR, and the resulting library was expressed in S. cerevisiae. The S. cerevisiae library expressing the mutant XR was selected in sequential anaerobic... (More)
- Baker's yeast (Saccharomyces cerevisiae) has been genetically engineered to ferment the pentose sugar xylose present in lignocellulose biomass. One of the reactions controlling the rate of xylose utilization is catalyzed by xylose reductase (XR). In particular, the cofactor specificity of XR is not optimized with respect to the downstream pathway, and the reaction rate is insufficient for high xylose utilization in S. cerevisiae. The current study describes a novel approach to improve XR for ethanol production in S. cerevisiae. The cofactor binding region of XR was mutated by error-prone PCR, and the resulting library was expressed in S. cerevisiae. The S. cerevisiae library expressing the mutant XR was selected in sequential anaerobic batch cultivation. At the end of the selection process, a strain (TMB 3420) harboring the XR mutations N272D and P275Q was enriched from the library. The V-max of the mutated enzyme was increased by an order of magnitude compared to that of the native enzyme, and the NADH/NADPH utilization ratio was increased significantly. The ethanol productivity from xylose in TMB 3420 was increased similar to 40 times compared to that of the parent strain (0.32 g/g [dry weight {DW}] x h versus 0.007 g/g [DW] x h), and the anaerobic growth rate was increased from similar to 0 h(-1) to 0.08 h(-1). The improved traits of TMB 3420 were readily transferred to the parent strain by reverse engineering of the mutated XR gene. Since integrative vectors were employed in the construction of the library, transfer of the improved phenotype does not require multicopy expression from episomal plasmids. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1752662
- author
- Runquist, David LU ; Hahn-Hägerdal, Bärbel LU and Bettiga, Maurizio LU
- organization
- publishing date
- 2010
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Applied and Environmental Microbiology
- volume
- 76
- issue
- 23
- pages
- 7796 - 7802
- publisher
- American Society for Microbiology
- external identifiers
-
- wos:000284310500014
- scopus:78650327471
- pmid:20889775
- pmid:20889775
- ISSN
- 0099-2240
- DOI
- 10.1128/AEM.01505-10
- language
- English
- LU publication?
- yes
- id
- 7b04ed2d-5a68-4ad9-8a44-72af7893f547 (old id 1752662)
- date added to LUP
- 2016-04-01 09:49:02
- date last changed
- 2022-04-11 23:11:36
@article{7b04ed2d-5a68-4ad9-8a44-72af7893f547,
abstract = {{Baker's yeast (Saccharomyces cerevisiae) has been genetically engineered to ferment the pentose sugar xylose present in lignocellulose biomass. One of the reactions controlling the rate of xylose utilization is catalyzed by xylose reductase (XR). In particular, the cofactor specificity of XR is not optimized with respect to the downstream pathway, and the reaction rate is insufficient for high xylose utilization in S. cerevisiae. The current study describes a novel approach to improve XR for ethanol production in S. cerevisiae. The cofactor binding region of XR was mutated by error-prone PCR, and the resulting library was expressed in S. cerevisiae. The S. cerevisiae library expressing the mutant XR was selected in sequential anaerobic batch cultivation. At the end of the selection process, a strain (TMB 3420) harboring the XR mutations N272D and P275Q was enriched from the library. The V-max of the mutated enzyme was increased by an order of magnitude compared to that of the native enzyme, and the NADH/NADPH utilization ratio was increased significantly. The ethanol productivity from xylose in TMB 3420 was increased similar to 40 times compared to that of the parent strain (0.32 g/g [dry weight {DW}] x h versus 0.007 g/g [DW] x h), and the anaerobic growth rate was increased from similar to 0 h(-1) to 0.08 h(-1). The improved traits of TMB 3420 were readily transferred to the parent strain by reverse engineering of the mutated XR gene. Since integrative vectors were employed in the construction of the library, transfer of the improved phenotype does not require multicopy expression from episomal plasmids.}},
author = {{Runquist, David and Hahn-Hägerdal, Bärbel and Bettiga, Maurizio}},
issn = {{0099-2240}},
language = {{eng}},
number = {{23}},
pages = {{7796--7802}},
publisher = {{American Society for Microbiology}},
series = {{Applied and Environmental Microbiology}},
title = {{Increased Ethanol Productivity in Xylose-Utilizing Saccharomyces cerevisiae via a Randomly Mutagenized Xylose Reductase}},
url = {{http://dx.doi.org/10.1128/AEM.01505-10}},
doi = {{10.1128/AEM.01505-10}},
volume = {{76}},
year = {{2010}},
}