Production of 2,3-butanediol in Saccharomyces cerevisiae by in silico aided metabolic engineering

Microbial Cell Factories

Research

ChiamYu Ng¹  Moo-young Jung¹  Min-Kyu Oh¹  Jinwon Lee² 

[1] Department of Chemical & Biological Engineering, Korea University, 136-701, Seoul, Republic of Korea;Department of Chemical & Biomolecular Engineering, Sogang University, 121-742, Seoul, Republic of Korea;

关键词: 2,3-Butanediol;    Saccharomyces cerevisiae;    Metabolic engineering;    Flux balance analysis;    Alcohol dehydrogenase;    OptKnock;   

DOI  :  10.1186/1475-2859-11-68

 received in 2011-12-13, accepted in 2012-05-04,  发布年份 2012

来源: Springer

【 摘 要 】

Background2,3-Butanediol is a chemical compound of increasing interest due to its wide applications. It can be synthesized via mixed acid fermentation of pathogenic bacteria such as Enterobacter aerogenes and Klebsiella oxytoca. The non-pathogenic Saccharomyces cerevisiae possesses three different 2,3-butanediol biosynthetic pathways, but produces minute amount of 2,3-butanediol. Hence, we attempted to engineer S. cerevisiae strain to enhance 2,3-butanediol production.ResultsWe first identified gene deletion strategy by performing in silico genome-scale metabolic analysis. Based on the best in silico strategy, in which disruption of alcohol dehydrogenase (ADH) pathway is required, we then constructed gene deletion mutant strains and performed batch cultivation of the strains. Deletion of three ADH genes, ADH1, ADH3 and ADH5, increased 2,3-butanediol production by 55-fold under microaerobic condition. However, overproduction of glycerol was observed in this triple deletion strain. Additional rational design to reduce glycerol production by GPD2 deletion altered the carbon fluxes back to ethanol and significantly reduced 2,3-butanediol production. Deletion of ALD6 reduced acetate production in strains lacking major ADH isozymes, but it did not favor 2,3-butanediol production. Finally, we introduced 2,3-butanediol biosynthetic pathway from Bacillus subtilis and E. aerogenes to the engineered strain and successfully increased titer and yield. Highest 2,3-butanediol titer (2.29 g·l-1) and yield (0.113 g·g-1) were achieved by Δadh1 Δadh3 Δadh5 strain under anaerobic condition.ConclusionsWith the aid of in silico metabolic engineering, we have successfully designed and constructed S. cerevisiae strains with improved 2,3-butanediol production.

【 授权许可】

Unknown   
© Ng et al.; licensee BioMed Central Ltd. 2012. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.