Metabolic engineering to enhance photosynthesis based on empirical data and in silico modelling

世界对粮食的需求正在增长，据估计，由于人口增长，粮食产量需要增加50%才能满足日益增长的需求。气候变化和对植物作为生物燃料的竞争性需求进一步加剧了这种情况。光合作用是植物利用来自太阳的能量将大气中的二氧化碳转化为碳水化合物和其他用于生长的化合物的过程。在过去的十年中，许多在高浓度二氧化碳环境中生长的植物实验明确表明，光合作用碳同化速率的增加可以导致生物量的增加。此外，在20世纪90年代进行的转基因实验中，单个酶的活性被上调或下调，提供的信息表明，操纵卡尔文循环可以影响植物的组成和提高植物的生产力。这些研究清楚地表明光合作用碳同化是一个未开发的增产机会。在本项目中，我们将基于经验数据、代谢和网络建模相结合，生产具有改变光合特性的转基因拟南芥植株。将对所得品系进行详细的生理和分子分析，以获得温室栽培植物光合参数和生长的详细测量。在这个项目中产生的具有改变光合碳代谢的转基因植物将用于探索二氧化碳同化、碳储存与植物生长之间的关系。这些分析将为进一步研究和改进这些模型提供数据。这项研究还将提供一个概念的证明，并将形成对作物进行知情操作的基础。

World demand for food is growing and it has been estimated that a 50% increase in yield will be needed to meet the increasing demand due to growing population. The changing climate and the competing demand for plants as biofuels further exacerbates this situation. Photosynthesis is the process by which plants use the energy from the sun to convert carbon dioxide from the atmosphere into carbohydrates and other chemical compounds, which are used for growth. Over the last decade numerous experiments of plants grown in elevated CO2 have shown unambiguously that increased rates of photosynthetic carbon assimilation can lead to increased biomass. Furthermore transgenic experiments conducted during the 1990's in which activities of individual enzymes were up- or down- regulated provided information showing that manipulation of the Calvin cycle could influence plant composition and increase plant productivity. These studies clearly identified photosynthetic carbon assimilation as an untapped opportunity to increase yield. In this project we will produce transgenic Arabidopsis plants with altered photosynthetic characteristics based on a combination of empirical data, metabolic and network modeling. A detailed physiological and molecular analysis of the resulting lines will carried out to obtain detailed measurements of photosynthetic parameters and growth in greenhouse grown plants. The transgenic plants generated in this programme with altered photosynthetic carbon metabolism will be used to explore the relationships between CO2 assimilation, carbon storage and plant growth. These analyses will provide data for further interrogation and improvement of these models. This research will also provide a proof of concept and will form the basis to enable informed manipulation of crop plants.