CAREER: Integrating Chemical and Biological Catalysis for the Sustainable Production of Biofuels and Commodity Chemicals

CBET 1149678 -Pfleger生物技术，生物化学和生物质工程计划的NSF CAREER奖支持一种将木质纤维素生物质转化为燃料和化学品的新方法，该方法绕过了以葡萄糖为中心的工艺中使用的酶糖化。PI假设，通过将木质纤维素材料转化为乙酰丙酸而不是葡萄糖，然后使用合成生物学和代谢工程的组合来开发微生物，以有效地将乙酰丙酸转化为所需的烃燃料或化学品，可以开发出潜在的更经济的生物燃料和生物可再生化学工艺。 由于乙酰丙酸可以通过木质纤维素生物质的酸水解以高产率生产，因此这种生物燃料和生物可再生化学品的路线避免了传统工艺中将生物质转化为可发酵糖所需的昂贵酶促降解步骤。研究团队将使用合成生物学对细菌进行代谢工程，以分解乙酰丙酸作为生长和合成直接碳氢化合物燃料的唯一碳源。拟议的工作将阐明一个以前未知的生化途径，检查工程催化剂的方法，并评估一个替代的生物质到化学品的过程。该提案是在以往利用大肠杆菌过量生产脂肪酸类产品的基础上，整合了代谢模型、生物化学、系统生物学和基因工程等方法，培养具备代谢工程和合成生物学应用能力的新一代化学工程师，以实现可持续的化学生产过程。为了迎接这一挑战，PI将重新设计生物化学工程的实验室课程，将继续发展iGEM计划（国际遗传工程机器），作为UWMadison跨学科研究和教育的典范。通过iGEM，本科团队设计，进行和交流合成生物学领域的实验研究项目，并将与NSF赞助的三角洲计划合作，开发教育材料，向年轻学生介绍可持续发展，生物能源，工程和合成生物学的概念。

CBET 1149678 - PflegerThis NSF CAREER award by the Biotechnology, Biochemical and Biomass Engineering program supports a novel approach to converting lignocellulosic biomass to fuels and chemicals that bypasses enzymatic saccharification used in glucose centric processes. The PI hypothesizes that potentially more economical biofuel and biorenewable chemical processes can be developed by converting lignocellulosic materials to levulinic acid instead of glucose, and then using a combination of synthetic biology and metabolic engineering to develop microoganisms to efficiently convert levulinic acid into the desired hydrocarbon fuel or chemical. Since levulinic acid can be produced in high yields via the acid hyrolysis of lignocellulose biomass, this route to biofuels and biorenewable chemicals avoids the costly enzymatic degradation steps needed in traditional processes to convert biomass into fermentable sugars.The research team will use synthetic biology to metabolically engineer a bacterium to catabolize levulinic acid as the sole carbon source for growth and the synthesis of drop-in hydrocarbon fuels. The proposed work will elucidate a previously unknown biochemical pathway, examine methods of engineering catabolism, and evaluate an alternative biomass-to-chemicals process. The proposal builds upon past work to engineer Escherichia coli to overproduce fatty-acid based products and integrates established metabolic modeling, biochemistry, systems biology, and genetic engineering approaches.The development of sustainable chemical production processes will require the training of a new generation of chemical engineers possessing the ability to apply metabolic engineering and synthetic biology. To meet this challenge, the PI will redesign a laboratory course in biochemical engineering, will continue the development of the iGEM program (international Genetically Engineered Machines) as a model for interdisciplinary research and education at UWMadison. Through iGEM, undergraduate teams design, conduct, and communicate experimental research projects in the field of synthetic biology, and will partner with the NSF-sponsored Delta program to develop educational materials for introducing younger students to the concepts of sustainability, bioenergy, engineering, and synthetic biology.