Tags

Type your tag names separated by a space and hit enter

Minimization of glycerol synthesis in industrial ethanol yeast without influencing its fermentation performance.
Metab Eng. 2011 Jan; 13(1):49-59.ME

Abstract

To synthesize glycerol, a major by-product during anaerobic production of ethanol, the yeast Saccharomyces cerevisiae would consume up to 4% of the sugar feedstock in typical industrial ethanol processes. The present study was dedicated to decreasing the glycerol production mostly in industrial ethanol producing yeast without affecting its desirable fermentation properties including high osmotic and ethanol tolerance, natural robustness in industrial processes. In the present study, the GPD1 gene, encoding NAD+-dependent glycerol-3-phosphate dehydrogenase in an industrial ethanol producing strain of S. cerevisiae, was deleted. Simultaneously, a non-phosphorylating NADP+-dependent glyceraldehyde-3-phosphate dehydrogenase (GAPN) from Bacillus cereus was expressed in the mutant deletion of GPD1. Although the resultant strain AG1A (gpd1△ P(PGK)-gapN) exhibited a 48.7±0.3% (relative to the amount of substrate consumed) lower glycerol yield and a 7.6±0.1% (relative to the amount of substrate consumed) higher ethanol yield compared to the wild-type strain, it was sensitive to osmotic stress and failed to ferment on 25% glucose. However, when trehalose synthesis genes TPS1 and TPS2 were over-expressed in the above recombinant strain AG1A, its high osmotic stress tolerance was not only restored but also improved. In addition, this new recombinant yeast strain displayed further reduced glycerol yield, indistinguishable maximum specific growth rate (μ(max)) and fermentation ability compared to the wild type in anaerobic batch fermentations. This study provides a promising strategy to improve ethanol yields by minimization of glycerol production.

Links

Publisher Full Text

Authors+Show Affiliations

Guo ZP
The Key Laboratory of Industrial Biotechnology, Ministry of Education, Center for Bioresources & Bioenergy, School of Biotechnology, Jiangnan University, Wuxi 214122, PR China.
Zhang L
No affiliation info available
Ding ZY
No affiliation info available
Shi GY
No affiliation info available

MeSH

EthanolFermentationGenetic EnhancementGlycerolGlycerol-3-Phosphate Dehydrogenase (NAD+)IndustrySaccharomyces cerevisiaeSaccharomyces cerevisiae Proteins

Pub Type(s)

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

Language

eng

PubMed ID

21126600

Citation

Guo, Zhong-peng, et al. "Minimization of Glycerol Synthesis in Industrial Ethanol Yeast Without Influencing Its Fermentation Performance." Metabolic Engineering, vol. 13, no. 1, 2011, pp. 49-59.
Guo ZP, Zhang L, Ding ZY, et al. Minimization of glycerol synthesis in industrial ethanol yeast without influencing its fermentation performance. Metab Eng. 2011;13(1):49-59.
Guo, Z. P., Zhang, L., Ding, Z. Y., & Shi, G. Y. (2011). Minimization of glycerol synthesis in industrial ethanol yeast without influencing its fermentation performance. Metabolic Engineering, 13(1), 49-59. https://doi.org/10.1016/j.ymben.2010.11.003
Guo ZP, et al. Minimization of Glycerol Synthesis in Industrial Ethanol Yeast Without Influencing Its Fermentation Performance. Metab Eng. 2011;13(1):49-59. PubMed PMID: 21126600.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Minimization of glycerol synthesis in industrial ethanol yeast without influencing its fermentation performance. AU - Guo,Zhong-peng, AU - Zhang,Liang, AU - Ding,Zhong-yang, AU - Shi,Gui-yang, Y1 - 2010/11/30/ PY - 2010/08/31/received PY - 2010/11/08/revised PY - 2010/11/16/accepted PY - 2010/12/4/entrez PY - 2010/12/4/pubmed PY - 2011/4/16/medline SP - 49 EP - 59 JF - Metabolic engineering JO - Metab Eng VL - 13 IS - 1 N2 - To synthesize glycerol, a major by-product during anaerobic production of ethanol, the yeast Saccharomyces cerevisiae would consume up to 4% of the sugar feedstock in typical industrial ethanol processes. The present study was dedicated to decreasing the glycerol production mostly in industrial ethanol producing yeast without affecting its desirable fermentation properties including high osmotic and ethanol tolerance, natural robustness in industrial processes. In the present study, the GPD1 gene, encoding NAD+-dependent glycerol-3-phosphate dehydrogenase in an industrial ethanol producing strain of S. cerevisiae, was deleted. Simultaneously, a non-phosphorylating NADP+-dependent glyceraldehyde-3-phosphate dehydrogenase (GAPN) from Bacillus cereus was expressed in the mutant deletion of GPD1. Although the resultant strain AG1A (gpd1△ P(PGK)-gapN) exhibited a 48.7±0.3% (relative to the amount of substrate consumed) lower glycerol yield and a 7.6±0.1% (relative to the amount of substrate consumed) higher ethanol yield compared to the wild-type strain, it was sensitive to osmotic stress and failed to ferment on 25% glucose. However, when trehalose synthesis genes TPS1 and TPS2 were over-expressed in the above recombinant strain AG1A, its high osmotic stress tolerance was not only restored but also improved. In addition, this new recombinant yeast strain displayed further reduced glycerol yield, indistinguishable maximum specific growth rate (μ(max)) and fermentation ability compared to the wild type in anaerobic batch fermentations. This study provides a promising strategy to improve ethanol yields by minimization of glycerol production. SN - 1096-7184 UR - https://www.unboundmedicine.com/medline/citation/21126600/Minimization_of_glycerol_synthesis_in_industrial_ethanol_yeast_without_influencing_its_fermentation_performance_ L2 - https://linkinghub.elsevier.com/retrieve/pii/S1096-7176(10)00101-1 DB - PRIME DP - Unbound Medicine ER -