SusChEM: Design of Ionic-Liquid-Biocatalyst Systems for Production of Platform Chemicals and Intermediates Directly from Plant Biomass

未来，为了使生物炼油厂经济地运行，它们将需要一个完整的过程，充分利用木质纤维生物质中的所有碳，包括纤维素、半纤维素和木质素来生产生物燃料、生物化学品和生物材料。然而，生物质很难加工。离子液体(IL)预处理是一种新兴的生物质加工辅助技术。为了成功商业化，这项技术必须克服重大障碍，即ILS的成本、回收费用和对生物催化剂的一般毒性。为了克服这些障碍，本研究的目标是开发新型的高度兼容的IL-生物催化剂系统，用于木质纤维生物质同时糖化和发酵(SSF-IL)生成高价值有机化学品(HVO)。具体地说，该团队将从根本上研究和优化解脂Yarrowia的高IL耐受性，这是一种通常被认为是安全的油性酵母，它可以在至少10%的IL溶液中茁壮成长并进行高效的生物转化。该团队还将阐明和优化解脂耶尔森菌的代谢，以有效地共同利用葡萄糖和木糖，这是木质纤维生物质的主要糖类。最后，该团队将开发高度兼容的IL-生物催化剂系统，以促进木质纤维杂交杨(一种潜在的生物能源作物)通过SSF-IL转化为高价值有机物，特别是α-酮戊二酸。该项目将获得对工程IL-生物催化系统如何将顽固的生物质转化为有价值的生物燃料、生物化学品和生物材料的基本了解，并展示一个非传统、经济和具有竞争力的综合生物炼油厂的模型。它将通过利用可再生、可持续和国产木质纤维素生物质替代化石燃料，为能源独立、安全和更绿色的环境提供一条有前景的可持续途径。该项目还将提供教育部分，包括在生物质转化、生物催化、系统生物学和代谢工程领域对博士后、研究生和(代表不足的少数族裔)本科生进行培训。此外，外展将包括让本科生参与国际基因工程机械(IGEM)项目，该项目自2012年以来一直由PI组织，并为K-12学生组织暑期研讨会，这些学生将接触到催化和生物催化的各个方面，以解决与能源相关的挑战性问题。该项目由美国国家科学基金会激励竞争研究实验计划(EPSCoR)共同资助。

In the future, for biorefineries to operate economically, they will require an integrated process with the complete use of all carbons in the lignocellulosic biomass including cellulose, hemicellulose, and lignin to produce biofuels, biochemicals, and biomaterials. Biomass is difficult to process, however. Ionic liquid (IL) pretreatment is an emerging technology that aids biomass processing. For its successful commercialization, this technology must overcome significant barriers, namely cost of the ILs, recycling expense, and general toxicity to biocatalysts. To tackle these barriers, the objective of the proposed research is to develop novel highly-compatible IL-biocatalyst systems for simultaneous saccharification and fermentation (SSF-IL) of lignocellulosic biomass into high-value organic chemicals (HVOs). Specifically, the team will fundamentally study and optimize high IL-tolerance of Yarrowia lipolytica, a generally regarded-as-safe oleaginous yeast, that can thrive and perform efficient biotransformation in at least a 10% IL solution. The team will also elucidate and optimize Y. lipolytica metabolism for efficient co-utilization of glucose and xylose, the major sugars of lignocellulosic biomass. Finally, the team will develop highly compatible IL-biocatalyst systems for enhanced conversion of lignocellulosic hybrid poplar (a potential bioenergy crop), into high-value organics, specifically alpha-ketoglutaric acid via SSF-IL.The project will gain fundamental understanding of how the engineered IL-biocatalyst system can transform recalcitrant biomass into valuable biofuels, biochemicals, and biomaterials, and demonstrate a model for an unconventional, economical, and competitive integrated biorefinery. It will present a promising sustainable pathway for energy independence, security, and a greener environment by utilizing renewable, sustainable, and domestic lignocellulosic biomass instead of fossil fuels. The project will also provide educational components including training of postdoctoral, graduate and (underrepresented minority) undergraduate students in the areas of biomass conversion, biocatalysis, systems biology, and metabolic engineering. In addition, outreach will involve engaging undergraduate students in the Internationally Genetically Engineered Machinery (iGEM) program that the PI has organized since 2012 as well as organizing summer workshops for K-12 students who will be exposed to various aspects of Catalysis and Biocatalysis to address challenging energy-related problems. The project is co-funded by the NSF Experimental Program to Stimulate Competitive Research (EPSCoR).