Engineered Microbial Systems for Conversion of Biomass Hydrolysates

该项目将为糖混合物（戊糖和己糖）在乙酸等抑制剂存在下有效转化为生化产物提供一种新方法。在建议的工作中，这种复杂的混合物提出的挑战是通过工程的微生物系统，其中的转换发生解决。该概念依赖于只能代谢单一碳源（如糖木糖或乙酸）的微生物菌株的构建，并使用这些“底物选择性”菌株设计有效的过程。除了构建和表征一套底物选择性菌株外，还将开发和优化工艺，以从含有乙酸和五种主要糖的木质纤维素水解物中生成两种模型生化物质，乙醇和丙酮酸。更广泛的影响虽然重点将是乙醇和丙酮酸生产，但正在开发的策略可用于任何微生物产品，实际上是任何微生物，因此该研究广泛适用于许多系统。这种方法构成了一种为复杂混合物设计微生物系统的新方法。这项提议的工作是分子生物学和过程工程学生、教育工作者以及高中生之间跨学科的努力，旨在改善生物质利用的生产和加工技术。

0929893EitemanIntellectual merit This project will lead to a novel approach for the efficient conversion of sugar mixtures (pentoses and hexoses) to biochemical products in the presence of inhibitors such as acetic acid. In the proposed work the challenges this complex mixture presents are addressed by engineering the microbial system in which the conversion takes place. The concept relies on the construction of microbial strains which can only metabolize a single carbon source (such as the sugar xylose or acetic acid), and designing an efficient process using these "substrate-selective" strains. In addition to constructing and characterizing a suite of substrate-selective strains, processes will be developed and optimized to generate two model biochemicals, ethanol and pyruvate, from lignocellulosic hydrolysates which contain acetic acid and the five principal sugars.Broader impactsAlthough the focus will be ethanol and pyruvate production, the strategy being developed can be used for any microbial product and indeed any microorganism, and therefore the research is broadly applicable to numerous systems. This approach constitutes a new approach toward engineering a system of microbes for a complex mixture. The proposed work constitutes an interdisciplinary effort between molecular biology and process engineering students, educators as well as high school students toward improving production and processing technologies for the use of biomass.