Tags

Type your tag names separated by a space and hit enter

Implementation of a transhydrogenase-like shunt to counter redox imbalance during xylose fermentation in Saccharomyces cerevisiae.
Appl Microbiol Biotechnol. 2013 Feb; 97(4):1669-78.AM

Abstract

Three enzymes responsible for the transhydrogenase-like shunt, including malic enzyme (encoded by MAE1), malate dehydrogenase (MDH2), and pyruvate carboxylase (PYC2), were overexpressed to regulate the redox state in xylose-fermenting recombinant Saccharomyces cerevisiae. The YPH499XU/MAE1 strain was constructed by overexpressing native Mae1p in the YPH499XU strain expressing xylose reductase and xylitol dehydrogenase from Scheffersomyces stipitis, and native xylulokinase. Analysis of the xylose fermentation profile under semi-anaerobic conditions revealed that the ethanol yield in the YPH499XU/MAE1 strain (0.38 ± 0.01 g g⁻¹ xylose consumed) was improved from that of the control strain (0.31 ± 0.01 g g⁻¹ xylose consumed). Reduced xylitol production was also observed in YPH499XU/MAE1, suggesting that the redox balance was altered by Mae1p overexpression. Analysis of intracellular metabolites showed that the redox imbalance during xylose fermentation was partly relieved in the transformant. The specific ethanol production rate in the YPH499XU/MAE1-MDH2 strain was 1.25-fold higher than that of YPH499XU/MAE1 due to the additional overexpression of Mdh2p, whereas the ethanol yield was identical to that of YPH499XU/MAE1. The specific xylose consumption rate was drastically increased in the YPH499XU/MAE1-MDH2-PYC2 strain. However, poor ethanol yield as well as increased production of xylitol was observed. These results demonstrate that the transhydrogenase function implemented in S. cerevisiae can regulate the redox state of yeast cells.

Authors+Show Affiliations

Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe, Hyogo 657-8501, Japan.No affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

22851014

Citation

Suga, Hiroyuki, et al. "Implementation of a Transhydrogenase-like Shunt to Counter Redox Imbalance During Xylose Fermentation in Saccharomyces Cerevisiae." Applied Microbiology and Biotechnology, vol. 97, no. 4, 2013, pp. 1669-78.
Suga H, Matsuda F, Hasunuma T, et al. Implementation of a transhydrogenase-like shunt to counter redox imbalance during xylose fermentation in Saccharomyces cerevisiae. Appl Microbiol Biotechnol. 2013;97(4):1669-78.
Suga, H., Matsuda, F., Hasunuma, T., Ishii, J., & Kondo, A. (2013). Implementation of a transhydrogenase-like shunt to counter redox imbalance during xylose fermentation in Saccharomyces cerevisiae. Applied Microbiology and Biotechnology, 97(4), 1669-78. https://doi.org/10.1007/s00253-012-4298-3
Suga H, et al. Implementation of a Transhydrogenase-like Shunt to Counter Redox Imbalance During Xylose Fermentation in Saccharomyces Cerevisiae. Appl Microbiol Biotechnol. 2013;97(4):1669-78. PubMed PMID: 22851014.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Implementation of a transhydrogenase-like shunt to counter redox imbalance during xylose fermentation in Saccharomyces cerevisiae. AU - Suga,Hiroyuki, AU - Matsuda,Fumio, AU - Hasunuma,Tomohisa, AU - Ishii,Jun, AU - Kondo,Akihiko, Y1 - 2012/08/01/ PY - 2012/03/28/received PY - 2012/07/11/accepted PY - 2012/07/10/revised PY - 2012/8/2/entrez PY - 2012/8/2/pubmed PY - 2013/7/11/medline SP - 1669 EP - 78 JF - Applied microbiology and biotechnology JO - Appl Microbiol Biotechnol VL - 97 IS - 4 N2 - Three enzymes responsible for the transhydrogenase-like shunt, including malic enzyme (encoded by MAE1), malate dehydrogenase (MDH2), and pyruvate carboxylase (PYC2), were overexpressed to regulate the redox state in xylose-fermenting recombinant Saccharomyces cerevisiae. The YPH499XU/MAE1 strain was constructed by overexpressing native Mae1p in the YPH499XU strain expressing xylose reductase and xylitol dehydrogenase from Scheffersomyces stipitis, and native xylulokinase. Analysis of the xylose fermentation profile under semi-anaerobic conditions revealed that the ethanol yield in the YPH499XU/MAE1 strain (0.38 ± 0.01 g g⁻¹ xylose consumed) was improved from that of the control strain (0.31 ± 0.01 g g⁻¹ xylose consumed). Reduced xylitol production was also observed in YPH499XU/MAE1, suggesting that the redox balance was altered by Mae1p overexpression. Analysis of intracellular metabolites showed that the redox imbalance during xylose fermentation was partly relieved in the transformant. The specific ethanol production rate in the YPH499XU/MAE1-MDH2 strain was 1.25-fold higher than that of YPH499XU/MAE1 due to the additional overexpression of Mdh2p, whereas the ethanol yield was identical to that of YPH499XU/MAE1. The specific xylose consumption rate was drastically increased in the YPH499XU/MAE1-MDH2-PYC2 strain. However, poor ethanol yield as well as increased production of xylitol was observed. These results demonstrate that the transhydrogenase function implemented in S. cerevisiae can regulate the redox state of yeast cells. SN - 1432-0614 UR - https://www.unboundmedicine.com/medline/citation/22851014/Implementation_of_a_transhydrogenase_like_shunt_to_counter_redox_imbalance_during_xylose_fermentation_in_Saccharomyces_cerevisiae_ L2 - https://dx.doi.org/10.1007/s00253-012-4298-3 DB - PRIME DP - Unbound Medicine ER -