EFRI-PSBR: Integrated design of cyanobacterial biorefineries

该项目采用了几种新的系统方法和一种替代的目标生物燃料，以开发蓝藻生产燃料和化学品的可持续过程。该项目已被授予一个多学科团队，成员包括科罗拉多州立大学科罗拉多州立大学的肯尼斯·F·里尔登、大卫·S·丹迪、托马斯·H·布拉德利、克里斯蒂·A·皮布尔斯和格雷厄姆·皮尔斯教授。为了解决提高商品产量和增加光合作用微生物衍生燃料的可持续性的目标，研究小组将综合流体动力学、光合作用生理学、蛋白质组学、代谢工程和生命周期分析方法的知识和方法。在一种设计光合作用效率的新方法中，研究小组将对不同光生物反应器的环境进行建模，并使用这些模型为实验室培养设计精确的缩小系统，这与通常的做法相反。这将使他们能够在小范围内识别和瞄准与工业相关的生物学，并对大规模系统做出准确的预测。接下来，该团队将量化与光合作用相关的能量损失和压力，并将其用于基因改良。这项基因研究将与蓝藻的代谢工程相结合，将碳输送到一种新型的倍半萜燃料分子--双倍半萜，它有望成为一种替代生物柴油，而不需要目前从植物油中生产生物柴油所必需的酯交换过程。为了以节能的方式将蓝藻细胞从其培养液中分离出来，该团队将开发一种基于惯性迁移的新型细胞浓缩机制。所有这些关于系统性能的研究将以新的生命周期分析方法的反馈为指导，这些方法是通过使用本项目中开发的放大关系对大型反应堆的生产率进行建模而开发的。科罗拉多州立大学的团队预测，这种解决与基于光合作用的微生物燃料相关的主要问题的综合方法将导致快速提高控制系统生产力的准确性和速度；在工业部署中获得更大的目标分子产量；该过程的整体可持续性大幅、量化地增加；以及可转移的方法，用于培养光合作用微生物和生产其他生物燃料或生物化学品。更广泛的影响：拟议的工作包括了解光生物反应器过程动力学、蓝藻对光生物反应器条件的生理反应、蓝藻工程以生产生物燃料和生物化学品，以及生命周期分析，将导致光合作用生产具有环境可持续潜力的先进生物燃料和生物化学品。这些工程菌株将成为未来生物燃料升级战略和生化生产战略研究的平台。该项目将为本科生和研究生以及博士后学者提供跨学科培训，并正在作出重大努力，纳入代表性不足群体的成员。学生将在建模、代谢工程、系统生物学、光合作用生物的微生物细胞培养和生命周期分析方面获得广泛的经验，使学生处于光合作用生物生产生物燃料研究的前沿。该项目包括在研究和教师培训方面为K-12学生提供指导的机会。该项目的成果将在主要的同行评议期刊、国家会议、新课程中以及通过互动网站传播。

AbstractIntellectual Merit: Several novel systems approaches and an alternative target biofuel are brought to bear in this project to develop sustainable processes for the production of fuels and chemicals by cyanobacteria. The project has been awarded to a multidisciplinary team, consisting of Professors Kenneth F. Reardon, David S. Dandy, Thomas H. Bradley, Christie A.M. Peebles, and Graham Peers, all of Colorado State University, Fort Collins, CO. To address the goals of increasing commodity yields and increasing the sustainability of photosynthetic microbe-derived fuels, the research team will synthesize knowledge and approaches from fluid dynamics, photosynthetic physiology, proteomics, metabolic engineering, and life cycle analysis methods.In a novel approach to engineer photosynthetic efficiency, the team will model the environment of different photobioreactors and use these models to design accurate scale-down systems for laboratory cultivations, opposite to the usual practice. This will allow them to identify and target industrially relevant biology at a small scale and make accurate predictions for large-scale systems. Next, the team will quantify energy losses and stresses associated with photosynthesis, and target these for genetic improvements. This genetic research will be coupled to the metabolic engineering of cyanobacteria to shuttle carbon to a novel sesquiterpene fuel molecule, bisabolene, which offers promise as an alternative biodiesel which does not require transesterification processing, necessary in the current biodiesel production from vegetable oils. To separate the cyanobacterial cells from their cultivation liquid in an energy-efficient manner, the team will develop a novel inertial migration-based cell concentration mechanism. All of these studies on system performance will be guided by feedback from new life cycle analysis methods developed by modeling the productivity of large-scale reactors using the scale-up relationships developed in this project. The Colorado State team predicts this integrated approach to solving the major issues associated with photosynthetic microbe-based fuels will result in a rapid increase in the accuracy and speed with which the productivity of the system can be manipulated; greater yields of target molecules in industrial deployment; large, quantified increases in the overall sustainability of the process; and transferrable approaches toward the cultivation of photosynthetic microbes and the production of other biofuels or biochemicals. Broader Impacts: The proposed work, which encompasses understanding of photobioreactor process dynamics, physiological responses of cyanobacteria to photobioreactor conditions, engineering of cyanobacteria to produce biofuels and biochemicals, and life cycle analysis, will lead to photosynthetic production of advanced biofuels and biochemicals with the potential to be environmentally sustainable. The engineered strains will serve as a platform for future research on biofuel upgrading strategies and on biochemical production strategies. The project will provide interdisciplinary training for undergraduate and graduate students, as well as postdoctoral scholars, with significant efforts being made to include members of underrepresented groups. Students will gain broad experience in modeling, metabolic engineering, systems biology, microbial cell cultivation of photosynthetic organisms and life cycle analysis, placing the students at the forefront of research in biofuel production from photosynthetic organisms. The project includes opportunities for mentoring of K-12 students in research, as well as teacher training. The results of this project will be disseminated in leading peer-reviewed journals, national meetings, in new courses, and via an interactive website.