Combinatorial metabolic engineering platform for the production of valuable compounds in the alga Euglena gracilis

实现温室气体净零排放的可持续发展需要新技术来捕获二氧化碳并制造有价值的产品。光合藻类可以实现这一目标，将二氧化碳转化为生物质和高价值的化合物，如染料虾青素。藻类代谢工程的最新进展允许增加天然产物的产量，但也引入新的基因和途径，以产生对环境影响最小的所需化合物。纤细裸藻由于其复杂的进化历史、遗传和细胞多样性、独特的生物学和复杂的代谢而成为一种重要的藻类，使其能够产生多种代谢产物。对裸藻的工业兴趣已导致其用于生产生物燃料，由于其合成蜡酯，用于生物修复，由于其在广泛的环境中生长和螯合重金属的能力，以及用于生产营养补充剂，由于其合成多不饱和脂肪酸和β-葡聚糖。尽管代谢工程有机会在裸藻中产生高价值的生物分子，但有效的基因工程工具有限。建立了高效的转化方法和先进的合成生物学工具包，为大肠杆菌代谢工程提供了技术支持。gracilis将增加这种生物技术在工业生物技术中的价值，并为理解这组生物体的基础生物学提供工具。在这个项目中，学生将开发一个平台，用于组装和优化眼虫中的代谢途径，并将其应用于从大气CO2中生产高价值分子。为了控制和优化生产，涉及广泛的考虑因素，从蛋白质的细胞位置到它们的相对丰度和对生长的影响。学生将评估不同控制元素的相对生产水平，并开发诱导部件。他们将开发能够使用靶向肽或细胞器转化将蛋白质靶向正确亚细胞位置的部件。基于最近在其他生物体中取得的成功，使用不同部件库的组合组装将在所有阶段用于优化生产。学生将应用项目早期开发的工具，在眼虫中生产高价值的蛋白质和产品，用于工业或医药用途。最初的目标将是单一蛋白质，如用于药物用途的人促红细胞生成素，作为纳米技术支架的病毒核心蛋白质和用于合成高价值分子的单一酶，如萜烯卡连素。然后将开发出更复杂的生物合成途径，如抗疟药前体青蒿酸生物合成的三酶级联。将分析优化的生产平台在这些高价值化合物的环境友好型工业生产中的潜力。学生将获得藻类生物技术，合成生物学和代谢工程方面的培训。

Sustainable development with net zero greenhouse gas emissions will require new technologies to capture CO2 and make valuable products. Photosynthetic algae can realise this goal, turning CO2 into biomass and high value compounds, such as the dye astaxanthin. Recent advances in algal metabolic engineering allows yield increase for the natural products, but also the introduction of novel genes and pathways to make desired compounds with minimal environmental impact. Euglena gracilis is an important alga due to its complex evolutionary history, genetic and cellular diversity, unique biology, and intricate metabolism, allowing it to produce a wide array of metabolites. Industrial interest in Euglena has led to it being used for the production of biofuels, due to its synthesis of wax esters, for bioremediation, due to its ability to grow In a wide range of environments and sequester heavy metals, and for the production of nutritional supplements, due to its synthesis of polyunsaturated fatty acids and B-glucans. Despite the opportunities for metabolic engineering to produce high-value biomolecules in Euglena, efficient genetic engineering tools are limited. Establishing an efficient transformation method and advanced synthetic biology toolkit for metabolic engineering of E. gracilis would increase the value of this alga for industrial biotechnological, as well as provide tools for the understanding of fundamental biology in this group of organisms. In this project the student will develop a platform for assembly and optimisation of metabolic pathways in Euglena and apply them for the production of high value molecules from atmospheric CO2. In order to control and optimise the production, a wide range of considerations are involved, from the cellular location of the proteins to their relative abundance and the impact on growth. The student will evaluate relative production levels from different control elements and develop inducible parts. They will develop parts with the ability to target proteins to the correct subcellular location, using targeting peptides or organelle transformation. Building on recent successes in other organisms, combinatorial assembly using libraries of different parts will be used at all stages to optimise production.The student will apply the tools developed in the earlier parts of the project to produce high value proteins and products in Euglena for industrial or medicinal uses. Initial targets will be single proteins, such as the human erythropoietin for pharmaceutical use, viral core proteins as scaffolds for nanotechnology and single enzymes for the synthesis of high value molecules, such as the terpene caryophyllene. More complex biosynthetic pathways will then be developed, such as the three-enzyme cascade for the biosynthesis of the antimalarial precursor artemisinic acid. The optimised production platforms will be analysed for their potential for the environmentally friendly industrial production of these high value compounds. The student will gain training in algal biotechnology, synthetic biology and metabolic engineering.