Collaborative Research: Exploiting Prokaryotic Proteins to Improve Plant Photosynthetic Efficiency

合作研究：利用原核蛋白提高植物光合效率

• 批准号: 1105584
• 负责人: Maureen Hanson
• 金额: $ 67.53万
• 依托单位: Cornell University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-03-15 至 2015-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1105584&HistoricalAwards=false
• 关键词: Collaborative; Research; Exploiting; Prokaryotic; Proteins

Photorespiration can account for yield losses of 25-50% in C3 plants, which include rice, wheat and soybean, three of the top four crops in terms of global grain production. Photorespiration occurs because oxygen and carbon dioxide (CO2) compete for the same acceptor molecule in photosynthesis. The process can be very simply inhibited by increasing the concentration of CO2. When CO2 is increased artificially in greenhouses or in open fields, very significant yield increases are obtained. However, artificially elevating CO2 over millions of acres of fields is not feasible. Some cyanobacteria solve this problem by confining the fixation of carbon to a structure termed a carboxysome, where localization of specific enzymes cause a concentration of CO2. Although chloroplasts, which contain the photosynthetic machinery of crops, lack carboxysomes, they evolved from cyanobacteria, which were symbiotically recruited into the ancestors of todays plants and crops. This research project will provide the foundation for a synthetic biology approach in which carboxysomes will be engineered into the chloroplasts of crop plants to enhance photosynthesis. Optimization will involve manipulating a model plant that is readily transformable and the development of an in silico model of the system to evaluate the use of different proteins and the minimal system that is needed. A multidisciplinary approach will be implemented through collaboration of four research groups, each contributing complementary expertise: carboxysome genetics and assembly (Berkeley), chloroplast and nuclear transformation (Cornell), photosynthetic systems modelling (Illinois) and physiological and biochemical characterization of the whole plant (Rothamsted, Cornell and Illinois). The project will allow postdoctoral and undergraduate trainees to gain experience in an international collaborative project (All). Research resources for comparing plant and bacterial genes will be developed for use in undergraduate education (Berkeley).

光呼吸可以解释C3作物25%-50%的产量损失，其中包括水稻、小麦和大豆，这三种作物是全球粮食产量最大的四种作物之一。光呼吸的发生是因为氧气和二氧化碳(CO2)在光合作用中竞争同一受体分子。通过增加二氧化碳浓度，可以非常简单地抑制这一过程。当在温室或露地人工增加二氧化碳时，产量会获得非常显著的增加。然而，在数百万英亩的田地上人为地增加二氧化碳是不可行的。一些蓝藻通过将碳的固定限制在一种名为羧体的结构上来解决这个问题，在这种结构中，特定的酶的定位会导致二氧化碳浓度的增加。尽管包含作物光合作用机制的叶绿体缺乏羧基体，但它们是从蓝藻进化而来的，蓝藻是通过共生方式被招募到今天的植物和作物的祖先中的。这项研究项目将为合成生物学方法提供基础，在该方法中，将把羧基体工程到作物的叶绿体中，以增强光合作用。优化将包括操纵一个易于转化的模型植物，并开发一个系统的计算机模型，以评估不同蛋白质的使用和所需的最小系统。将通过四个研究小组的合作实施多学科方法，每个小组都提供互补的专门知识：羧体遗传学和组装(伯克利)、叶绿体和核转化(康奈尔大学)、光合作用系统模型(伊利诺伊州)和整个植物的生理和生化特征(罗萨姆斯特德、康奈尔和伊利诺伊州)。该项目将允许博士后和本科生在国际合作项目(ALL)中获得经验。比较植物和细菌基因的研究资源将被开发用于本科教育(伯克利)。