Fine-tuning the glycerol biosynthetic pathway in Saccharomyces cerevisiae to optimize the biotechnological production of bio-fuel ethanol and L-glycerol 3-phosphate (L-G3P)

微调酿酒酵母中的甘油生物合成途径，以优化生物燃料乙醇和 L-甘油 3-磷酸 (L-G3P) 的生物技术生产

• 批准号: 36207329
• 负责人: Professorin Dr. Elke Nevoigt
• 金额: --
• 依托单位: LISBP - Laboratoire dIngénierie des Systèmes Biologiques et des Procédés
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2007
• 资助国家: 德国
• 起止时间: 2006-12-31 至 2010-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/36207329?language=en
• 关键词: Fine; tuning; glycerol; biosynthetic; pathway

Bio-ethanol is a promising alternative to fossil fuels. Among the relevant avenues to increase conversion efficiency from biomass to ethanol, we want to focus on reducing the production of the main fermentation by-product glycerol. In addition to achieving higher ethanol yield, titer and specific productivity, such a metabolic pathway modification has the additional advantage to lower the costs for product recovery and reduces waste volumes. The challenge to reduce glycerol formation lies in the fact that the glycerol biosynthetic pathway has several important functions for cell growth and stress tolerance. Therefore, it is not straightforward to completely eliminate the glycerol biosynthetic pathway, and we want to address the challenge by fine-tuning enzyme activities in order to adjust metabolic fluxes according to cells’ minimal requirements. Without tax subsidies, bio-ethanol production is currently not an economically viable process. However, the economic efficiency could be markedly improved by concomitant production of high-value co-product(s). The L-enantiomer of glycerol 3-phosphate (L-G3P), is a high-price chemical with promising applications. Our lab has been successful in accumulating this substance in S. cerevisiae by metabolic engineering. We want to further improve L-G3P accumulation, and by doing so, evaluate the possibility of adding value to yeast biomass in the concept of bio-refining. L-G3P is an intermediate of the glycerol biosynthetic pathway. Hence, studies regarding its accumulation will synergistically affect research on reducing glycerol.

生物乙醇是一种很有前途的化石燃料替代品。在提高从生物质到乙醇的转化效率的相关途径中，我们希望专注于减少主要发酵副产物甘油的产生。除了实现更高的乙醇产率、滴度和比生产率之外，这种代谢途径修饰还具有降低产物回收成本和减少废物体积的额外优点。减少甘油形成的挑战在于甘油生物合成途径对细胞生长和胁迫耐受性具有几个重要功能。因此，完全消除甘油生物合成途径并不简单，我们希望通过微调酶活性来解决这一挑战，以便根据细胞的最低要求调整代谢通量。如果没有税收补贴，生物乙醇生产目前在经济上是不可行的。然而，通过同时生产高价值的副产品，可以显著提高经济效率。甘油3-磷酸的L-对映体（L-G3 P）是一种具有广阔应用前景的高价格化学品。我们的实验室已经成功地在S.酿酒酵母的代谢工程。我们希望进一步提高L-G3 P的积累，并通过这样做，评估在生物精炼概念中为酵母生物质增值的可能性。L-G3 P是甘油生物合成途径的中间体。因此，有关其积累的研究将协同影响减少甘油的研究。