SBIR Phase II: Novel Proteolysis-based Tools for Metabolic Engineering

这个小企业创新研究（SBIR）项目旨在设计微生物，以实现具有成本效益的特种化学品生产。目前，工程改造的微生物菌株具有突变，其通过抑制细胞产生途径外化学品的能力来增加感兴趣的化学品的产生。这些“功能丧失”突变是至关重要的，因为它们有效地引导细胞的代谢流流向感兴趣的产物。这既提高了生产效率，又通过消除不期望的但化学上相似的污染物的积累而使下游纯化容易。不幸的是，这些突变也可能降低细胞的适应性，因此，生长培养基必须补充昂贵的营养物质。本文的技术研究将评估应用新型调节蛋白水解技术的可行性，以同时将最大代谢通量导向感兴趣的目标化学品，同时避免需要补充生长培养基。如果成功，该技术将大大节省成本，并使发酵生产在特种化学品生产中得到更广泛的应用。该项目更广泛的影响/商业潜力是为特种化学品提供稳定且具有成本效益的发酵生产路线。 化学品的发酵生产提供了许多优于传统的石化或基于提取的生产工艺的优点。 石油化工产量保持全国？美国对不可持续的原料（石油）的依赖，也导致了国家安全问题，因为美国在很大程度上依赖外国石油来源。 通过从植物材料中提取的化学品生产也具有生态挑战。 该过程通常使用有毒溶剂，并且可能依赖于许多非传统粮食作物的不可持续的耕作方法。 在使用高效农业实践生产的糖原料上发酵的工程微生物为生产特种化学品提供了稳定的替代品，无论是在供应还是价格方面。

This Small Business Innovation Research (SBIR) project aims to engineer microbes for the cost-effective production of specialty chemicals. Currently, engineered microbial strains bear mutations that increase the production of chemicals of interest by inhibiting the cell's ability to produce off pathway chemicals. These "loss-of-function" mutations are critical as they effectively channel the cell's metabolic flux toward the product of interest. This both boosts the production efficiency and eases downstream purification by eliminating the accumulation of undesirable but chemically-similar contaminants. Unfortunately, these mutations may also decrease the fitness of the cells and, as a result, the growth media must be supplemented with costly nutrients. Technical research herein will assess the feasibility of applying novel regulated proteolysis technology to simultaneously direct maximal metabolic flux toward the target chemical of interest while avoiding the need to supplement the growth media. If successful, this technology would provide a great cost savings and enable fermentative production to be applied more broadly in the production of specialty chemicals.The broader impact/commercial potential of this project is to provide a stable and cost-effective fermentative production route to a specialty chemical. Fermentative production of chemicals offers many advantages over traditional petrochemical or extraction-based production processes. Petrochemical production maintains the nation?s reliance on an unsustainable feedstock (oil) and also leads to national security issues as the US is largely dependent on foreign oil sources. Chemical production via extraction from plant materials also has ecological challenges. The process often uses toxic solvents, and may rely on unsustainable farming practices for many plants that are not traditional food crops. Engineered microbes fermented on sugar feedstock produced using high-efficiency agricultural practices offer a stable alternative for producing specialty chemicals, both in terms of supply and price.