STTR Phase I: Metabolic engineering of photosynthesis for improved biomass accumulation

STTR 第一阶段：光合作用代谢工程以改善生物量积累

• 批准号: 1331974
• 负责人: Benjamin Gray
• 金额: $ 22.35万
• 依托单位: Benson Hill Biosystems, Inc.
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-07-01 至 2014-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1331974&HistoricalAwards=false
• 关键词: STTR; Phase; Metabolic; engineering; photosynthesis

This Small Business Technology Transfer (STTR) Phase I project proposes to improve intrinsic crop yield through metabolic engineering of photosynthetic pathways. Genes encoding five rate-limiting enzymes for photosynthesis and starch synthesis will be co-expressed constitutively or in a cell-specific manner in a model C4 plant species. Multiple metabolic pathways will be altered to simultaneously relieve multiple rate-limiting steps for carbon assimilation. The effects of enzyme accumulation on photosynthetic performance, plant growth, and biomass accumulation will be assayed, and optimal combinations of enzymes and relative enzyme levels will be determined. The effects of constitutive enzyme accumulation will be compared with cell-specific enzyme accumulation to determine whether a targeted expression profile can deliver a more substantial improvement in carbon assimilation rates and plant growth than constitutive enzyme accumulation. The results of this work will identify key rate-limiting enzymes in the photosynthetic machinery, optimal enzyme expression profiles, and optimal enzyme concentrations to improve photosynthetic performance, carbon assimilation, and yield.The broader impact/commercial potential of this project, if successful, will be to identify novel ways to improve crop yields in a range of both food and non-food crops. Photosynthetic engineering for improved carbon assimilation is a promising, but underexplored, method for improving intrinsic crop yield. Traditional plant biotechnology approaches have sought to protect yield, e.g. through insect resistance and herbicide tolerance. Utilizing synthetic biology to engineer primary metabolism and increase intrinsic crop yields will work in tandem with existing yield-protecting technologies. Modeling and initial proof-of-concept studies have confirmed that photosynthetic pathways can be engineered for greater efficiency, resulting in yield improvements. The results of this work will significantly enhance our understanding of the rate-limiting steps of photosynthetic carbon assimilation, providing insight into the most promising reactions and metabolic pathways for these engineering approaches. Translating the results of this Phase I work to crop plants will result in improved crop harvests without expanding the agricultural footprint, translating to enormous commercial benefits to the agricultural, food, and energy sectors.

这个小型企业技术转移（STTR）一期项目提出通过光合途径的代谢工程来提高作物内在产量。在模式C4植物物种中，编码光合作用和淀粉合成的五种限速酶的基因将以组成性或细胞特异性的方式共表达。多种代谢途径将被改变，同时减轻碳同化的多个速率限制步骤。将分析酶积累对光合性能、植物生长和生物量积累的影响，并确定酶的最佳组合和相对酶水平。组成酶积累的影响将与细胞特异性酶积累进行比较，以确定目标表达谱是否比组成酶积累在碳同化率和植物生长方面提供更实质性的改善。这项工作的结果将确定光合机制中的关键限速酶，最佳酶表达谱和最佳酶浓度，以提高光合性能，碳同化和产量。这个项目如果成功，其更广泛的影响/商业潜力将是确定提高一系列粮食和非粮食作物产量的新方法。改善碳同化的光合工程是一种很有前途但尚未开发的提高作物内在产量的方法。传统的植物生物技术方法寻求保护产量，例如通过抗虫和抗除草剂。利用合成生物学来设计初级代谢和提高作物固有产量将与现有的产量保护技术协同工作。模型和最初的概念验证研究已经证实，光合作用途径可以被设计成更高的效率，从而提高产量。这项工作的结果将大大提高我们对光合作用碳同化速率限制步骤的理解，为这些工程方法提供最有希望的反应和代谢途径。将第一阶段工作的成果转化为农作物，将在不扩大农业足迹的情况下提高作物收成，为农业、食品和能源部门带来巨大的商业利益。