Collaborative Research: Metabolically Engineered Organisms for Conversion of Cellulose to Isobutanol

合作研究：将纤维素转化为异丁醇的代谢工程生物体

• 批准号: 0903817
• 负责人: Frances Arnold
• 金额: $ 54.3万
• 依托单位: California Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-01 至 2013-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0903817&HistoricalAwards=false
• 关键词: Collaborative; Research; Metabolically; Engineered; Organisms

Meeting the world's rapidly growing energy needs while protecting Earth's increasingly threatened climate and ecological balance is one of the greatest challenges facing society. This project will explore a new route to producing an advanced liquid fuel from biomass by constructing a thermophilic microbial platform to convert cellulose to isobutanol. Compatible with current engines and with higher energy density, isobutanol is superior to ethanol as a fuel. Isobutanol can replace dwindling and politically unstable petroleum supplies without contributing to global warming and, unlike ethanol, can be incorporated into the energy economy using current technology and infrastructure. To target the fundamental hurdle in advanced biofuel research of utilizing cellulose as the feedstock, the goal will be to develop a thermophilic and (partially) cellulolytic Geobacillus host organism to produce cellulase(s) to augment the native cellulolytic activity. The ability of this organism to grow at the moderately elevated temperatures where cellulases are highly active and to utilize the sugar products of cellulose degradation that normally inhibit the cellulases will enhance performance and minimize the need for additional expensive enzyme addition during fermentation to generate biofuels. Specific objectives of this project will be to generate stable, active bacterial cellulases and express those new enzymes in Geobacillus. Simultaneously, the isobutanol pathway will be established in this moderately thermophilic host. The final goal will be to integrate and optimize cellulose degradation and isobutanol production pathways. Broader impacts: This research effort will train some of the most talented students and postdoctoral researchers in the world in protein and metabolic engineering, two technologies that are in very strong demand in the biotechnology industry, particularly the rapidly-growing biofuels/chemicals industry. This project will support extensive undergraduate research while interfacing with numerous outreach programs. The educational plan includes joint research meetings and co-advising of graduate students as well as the integration of parts of the research project into modules for laboratory courses. This project proposes a novel approach to addressing one of society's greatest challenges, developing a renewable source of transportation fuels and chemicals.

满足世界快速增长的能源需求，同时保护地球日益受到威胁的气候和生态平衡是社会面临的最大挑战之一。该项目将通过构建嗜热微生物平台将纤维素转化为异丁醇，探索一条利用生物质生产先进液体燃料的新路线。 异丁醇与当前发动机兼容且具有更高的能量密度，作为燃料优于乙醇。异丁醇可以取代日益减少且政治不稳定的石油供应，而不会导致全球变暖，并且与乙醇不同，异丁醇可以利用现有技术和基础设施纳入能源经济。为了解决利用纤维素作为原料的先进生物燃料研究的基本障碍，目标是开发一种嗜热且（部分）纤维素分解的地芽孢杆菌宿主生物体，以生产纤维素酶以增强天然纤维素分解活性。该生物体能够在纤维素酶高度活跃的适度升高的温度下生长，并利用通常抑制纤维素酶的纤维素降解的糖产物，这将增强性能并最大限度地减少在发酵过程中添加额外昂贵的酶以产生生物燃料的需要。该项目的具体目标是产生稳定、活性的细菌纤维素酶并在土芽孢杆菌中表达这些新酶。同时，异丁醇途径将在这个中等嗜热的宿主中建立。最终目标是整合和优化纤维素降解和异丁醇生产途径。更广泛的影响：这项研究工作将培养世界上蛋白质和代谢工程领域最有才华的学生和博士后研究人员，这两项技术在生物技术行业，特别是快速增长的生物燃料/化学品行业需求非常强劲。该项目将支持广泛的本科生研究，同时与众多外展项目相结合。教育计划包括联合研究会议和研究生共同指导，以及将部分研究项目整合到实验室课程模块中。该项目提出了一种新颖的方法来解决社会最大的挑战之一，即开发运输燃料和化学品的可再生来源。