Improving photosynthesis for biofuel production

氧光合作用被提议用于全球范围的燃料生产。为了使这一过程可行，需要较高的太阳能转换率。这一要求与光合效率有关，即太阳能转化为有机物质的效率。蓝藻是理想的生物燃料原料，因为它们生长在非农业和边缘土地上，并且能够在咸淡水和海水中茁壮成长。然而，尽管它们的理论最大能量转换效率估计为8-10%，但报告的最佳持续效率为1-2%。我们将研究蓝细菌的光收集以提高光合效率。我们将探讨二氧化碳如何与太阳能耦合，因为平衡源/汇能量是提高光合效率的一种策略。我们已经开发了鉴定二氧化碳结合蛋白的技术（Nature Communications (2018) 9:3092 DOI: 10.1038/s41467-018-05475-z）。这项技术可以识别功能蛋白（Science Advances (2021) 7:eabi5507）。我们已经在光收集复合体中发现了一种二氧化碳结合蛋白（Nature communications (2022) DOI: 10.1038/s41467-022-32925-6）。我们将研究二氧化碳结合对光收集的影响。我们建议操纵这一过程来改变源/汇能量，提高光合效率。年1。化学蛋白质组学和13C-NMR证明蛋白质二氧化碳结合。量子产率测量和超快飞秒光谱研究CO2对光捕获的影响。第二年。利用CRISPR:Cpf1诱变产生突变蓝藻菌株。使用稳态和时间分辨荧光光谱研究CO2对天然藻胆体和整个生物的光收集的影响。3 - 4年。研究生物乙醇产量的生产菌株，其中光收集已被工程与突变鉴定在目标2。

Oxygenic photosynthesis is proposed for fuel production on a global scale. A high solar energy conversion rate is needed to make the process feasible. This requirement is linked to the photosynthetic efficiency, i.e., the conversion efficiency of solar energy to organic material.The cyanobacteria are desirable biofuel feedstocks due to their growth on non-agricultural and marginal lands and ability to thrive in brackish and marine waters. However, although their theoretical maximum efficiency of energy conversion is estimated as 8-10%, the best-sustained efficiencies reported are 1-2%.We will investigate cyanobacterial light-harvesting to enhance photosynthetic efficiency. We will explore how carbon dioxide couples to solar energy, as balancing source/sink energies is a strategy for improving photosynthetic efficiency.We have developed technology for identifying CO2-binding proteins (Nature Communications (2018) 9:3092 DOI: 10.1038/s41467-018-05475-z). This technology can identify functional proteins (Science Advances (2021) 7:eabi5507).We have identified a CO2-binding protein in the light-harvesting complex (Nature Communcations (2022) DOI: 10.1038/s41467-022-32925-6). We will investigate the impact of CO2-binding on light-harvesting. We propose manipulating this process to alter source/sink energies and improve photosynthetic efficiency.Year 1. Chemical proteomics and 13C-NMR to demonstrate protein CO2-binding. Quantum yield measurements and ultrafast femtosecond spectroscopy to investigate the influence of CO2 on light-harvesting. Year 2. Generate mutant cyanobacterial strains using CRISPR:Cpf1 mutagenesis. Use steady-state and time-resolved fluorescence spectroscopy to investigate the impact of CO2 on light-harvesting in native phycobilisomes and whole organisms. Year 3-4. Investigate bio-ethanol yield in producing strains in which light-harvesting has been engineered with the mutations identified in Objective 2.