Collaborative Research: Plug and Play Photosynthesis for RuBisCO Independent Fuels

未来15年，全球人类能源消耗预计将增长30%以上。尽管阳光中的能量足以应对这一挑战，但将这种漫射的太阳能集中并储存起来的有效方法尚未被开发出来。光合作用是绿色植物和一些微生物捕获和储存太阳能的生物过程；它们利用它将二氧化碳转化为代谢燃料。然而，光合作用本质上是一个低效的过程；它不是受到来自太阳的光的可用性的限制，而是受到化学反应的第一步的速度的限制，通过这个反应，二氧化碳被转化为富含能量的产物。因此，通过自然光合作用捕获和利用太阳能的能力是未使用的。该项目吸引了来自美国和英国的研究团队，目标是通过提高效率来重新发明光合作用，从而提高光合作用生物制造可再生燃料和加强粮食安全的能力。在科研过程中，本项目将为超过14人（包括女性和少数民族）提供博士后、研究生和本科生的研究培训机会。该项目的国际性和跨学科性质将在包括合成生物学、光合生理学、催化和代谢调节在内的一系列重要科学领域建立美国和英国科学界之间的桥梁。研究人员将通过包括同行评审出版物、公共科学讲座、博客、网站和科普文章在内的活动，与公众和其他研究人员接触并向他们提供信息。为了显著提高光合作用的效率，该项目将开发一系列机制，将光活化的电子流从光合反应中心（PSI）电连接到下游的燃料生产途径。这将包括通过自然途径增加通量，通过构建人工生物纳米线在不同的微生物细胞类型之间建立电连接，以及采用可溶性化学氧化还原穿梭体将还原性当量从光收集细胞转移到不同的燃料生产细胞。这些科学目标将通过四个平行的具体目标来实现。1. 蓝藻胞外电子传递途径的组成和控制通量的机制的表征。构建从PSI中提取约化当量的人工系统它们只有在高度还原的条件下才会与天然电子受体竞争。3. 开发人工方法将还原性等价物移出聚囊藻的细胞质。在微生物内部构建人工燃料生产模块，只需要减少等效物和二氧化碳作为输入。该项目是高度跨学科的，将采用一系列技术，包括微生物学、分子生物学、合成生物学、生物化学、电化学、蛋白质和代谢工程。该奖项由分子和细胞生物科学部的细胞动力学和功能集群以及化学、生物工程、环境和运输系统部的生物技术、生化和生物质工程项目共同支持。

Global human energy consumption is expected to increase by over 30% in the next 15 years. Although there is more than enough energy in sunlight to meet this challenge, efficient means to concentrate this diffuse solar energy and store it have not yet been developed. Photosynthesis is the biological process by which green plants and some microorganisms capture and store solar energy; they use it to convert carbon dioxide to metabolic fuels. However, photosynthesis is inherently an inefficient process; it is limited not by the availability of light from the sun but by the rate of the first step in the chemical reactions by which carbon dioxide is converted into products that are rich in energy. There is therefore unused capacity for the capture and use of solar energy by natural photosynthesis. This program engages teams of researchers from the US and the United Kingdom with the goal to re-invent photosynthesis with enhanced efficiency thereby improving the capacity of photosynthetic organisms to make renewable fuels and enhance food security. In the course of the scientific research, this project will provide research training opportunities for more than 14 people (including both women and underrepresented minorities) at the post-doctoral, graduate and undergraduate levels. The international and interdisciplinary nature of the project will build bridges between the US and UK scientific communities in a range of important scientific areas including synthetic biology, photosynthetic physiology, catalysis, and metabolic regulation. The researchers will engage and inform both the public and other investigators through activities that include peer-reviewed publications, public science lectures, blogs, websites, and popular science articles. To dramatically enhance the efficiency of photosynthesis, this project will develop a range of mechanisms to electrically connect light-activated electron flow from the photosynthetic reaction center (PSI) to downstream fuel-production pathways. This will include increasing flux through natural pathways, creating electrical connections between distinct microbial cell types by construction of artificial biological nanowires, and employing a soluble, chemical, redox shuttle to transfer reducing equivalents from a light harvesting cell to different fuel-producing cells. These scientific goals will be accomplished through four parallel specific aims. 1. Characterization of the components of (and mechanism for controlling flux through) the natural extracellular electron transfer pathway of the cyanobacterium Synechocystis. 2. Construction of artificial systems to abstract reducing equivalents from PSI; these will compete with natural electron acceptors only under highly reducing conditions. 3. Development of artificial means to move reducing equivalents out of the cytoplasm of Synechocystis. 4. Construction within microbes of artificial fuel-production modules that require only reducing equivalents and carbon dioxide as inputs. The project is highly interdisciplinary and will employ a range of techniques including those from microbiology, molecular biology, synthetic biology, biochemistry, electrochemistry, and protein and metabolic engineering.This award is supported jointly by the Cellular Dynamics and Function Cluster in the Division of Molecular and Cellular Biosciences and by the Biotechnology, Biochemical and Biomass Engineering Program in the Division of Chemical, Bioengineering, Environmental and Transport Systems.