EAGER: Understanding the design principles of biological light harvesting

光合作用是地球上最强大的生物过程。 光合作用的第一步是通过生物天线以光的形式捕获能量。目前，设计和构建功能性生物天线的能力受到严重限制。该项目将大大推进生物天线在光合作用过程中如何捕获和转换光能的知识。 光合作用的产物，氧气和有机物，除了提供人类能源需求的重要部分外，还用于制造和驱动地球上几乎所有其他生命形式。由于光是一种扩散的能量来源，植物和其他光合微生物在其细胞中部署了大量的光捕获天线阵列，以将光集中到化学反应以高速率发生的特定位置。这些生物天线是由数百个光吸收分子结合在一起，以确保以近乎完美的效率运行。该提案将确定天线中的关键结构元素，并探索在细胞中对其进行工程改造的方法。了解生物光捕获的设计原理并开发构建新天线的方法将为改善作物中的光捕获系统并提高其生产力开辟新的途径。该项目将支持一名女博士后研究员和一名女研究生的职业生涯。此外，还将与当地学校一起制定一项旨在向儿童介绍科学、技术、工程、艺术和数学（STEAM）基本概念的方案。生物触角大多是膜结合的，含有数百种捕光色素。在细胞中构建功能性天线变体的能力是有限的，这阻碍了对天线在其自然环境中的理解，因为它们与光化学反应中心形成超级复合物。这项提议的重点是地球上一个名为IsiA的主要天线系统，它在蓝细菌门中很普遍。由于蓝细菌的多样性，大量的IsiA序列变体进化，并可以从公共数据库中检索。这项建议将探讨这种变异性的功能意义，通过引入嵌合天线到一个模型蓝藻。响应于应力，IsiA被诱导并在细胞中形成非常大且对称的天线组件。将测量嵌合天线形成这些组装体、进行能量转移和支持应激下的细胞生长的能力。研究结果将确定天线有助于细胞抵抗压力的机制，并将产生一个蜂窝平台，用于构建具有所需特性的新型天线系统。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Photosynthesis is the most powerful biological process on earth. The first step in photosynthesis is the capture of energy in the form of light by biological antenna. Currently, the ability to design and construct functional biological antenna is severely limited. This project will significantly advance the knowledge of how light energy is captured and converted by biological antenna during photosynthesis. The products of photosynthesis, oxygen and organic matter, are used to make and power virtually all other life forms on earth in addition to providing a significant portion of humanity’s energy needs. Because light is a diffuse energy source, plants and other photosynthetic microorganisms deploy large arrays of light harvesting antenna in their cells to concentrate light into specific locations where chemical reactions occur at high rates. These biological antennae are made from hundreds of light absorbing molecules held together in ways which ensures operation with near perfect efficiency. This proposal will identify the critical structural elements in antennae and explore ways to engineer them in cells. Understanding the design principles of biological light harvesting and developing methods to construct new antennae will open new ways to improve light harvesting systems in crops and increase their productivity. The project will support the career of one female post-doctoral fellow and one graduate student. In addition, a program aimed at introducing children into the basic concepts of Science, technology, engineering, art and mathematics (STEAM) will be developed with local schools. Biological antennae are mostly membrane bound and contain hundreds of light harvesting pigments. The ability to construct functional antenna variants in cells is limited and this hinders the understanding of antenna in their natural context, as they form super complexes with photochemical reaction centers. This proposal focuses on one of the major antennae systems on the planet called IsiA, which is prevalent in the cyanobacteria phylum. Due to the large diversity of cyanobacteria, a large number of IsiA sequence variants evolved and can be retrieved from public databases. This proposal will explore the functional significance of this variability by introducing chimeric antennae into a model cyanobacterium. In response to stress IsiA is induced and forms very large and symmetrical antennae assemblies in cells. The abilities of chimeric antennae to from these assemblies, to carry out energy transfer and to support cellular growth under stress will be measured. The results will identify the mechanisms by which antennae contribute to cellular resistance to stress and will generate a cellular platform for the construction of novel antennae systems with desired properties.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.