Engineering oilseeds to synthesise designer wax esters

蜡是一种具有有用性质的脂类，特别是作为润滑剂。现代工业世界依赖于(字面上)数以百万计的机器和流程的平稳运行，所有这些都需要润滑油来减少摩擦和磨损。目前，大多数润滑剂是由原油通过化学转化制成的，这一过程既作为原料又作为推动反应的能源消耗了这种宝贵的自然资源。换句话说，石油化学衍生的润滑剂是不可持续的。虽然植物种子产生油，但它们作为润滑剂并不是很有效，因为它们容易氧化，从而使它们变得粘性。然而，一种特殊的植物，荷荷巴，可以产生与所有其他植物种子中发现的不同级别的油。霍霍巴籽积累的是蜡酯，而不是三酰甘油，与正常的种子油相比，蜡的润滑性能要好得多。不幸的是，Jobaba植物只生长在美国的沙漠中，这就排除了它们在欧洲农业中的应用。为了绕过这个问题，我们建议将霍霍巴(和其他产生蜡酯的生物)的蜡生物合成基因转移到合适的植物物种上进行评估和测试。有人建议将拟南芥作为一个模型系统，以确定制造具有最有用特性的蜡的最佳基因组合，并在确定这些组合后，将其引入专门的工业油料作物--油菜(埃塞俄比亚芥菜)。重要的是，通过使用一种不用于生产食物的作物物种，这将确保我们的蜡质(用作生物清洗剂)不会进入人类食物链。总体而言，该项目旨在证明用植物来源的蜡酯替代石油化学来源的润滑油的可行性，为这些重要化合物提供一种新的绿色、可持续来源。

Waxes are a type of lipid which have useful properties, specially as lubricants. The modern industrial world is dependent (literally) on the smooth running of millions of machines and processes, all of which require lubricants to reduce friction and wear & tear. Currently, most lubricants are made from crude oil by chemical transformations, a process which consumes this deminishing natural resource both as a feedstock and as a source of energy to drive the reaction. In other words, petrochemically-derived lubricants are unsustainable. Whilst plant seeds produce oils, these are not very effective as lubricants as they are prone to oxidising which makes them sticky. However, one particular plant, jojoba, makes a different class of oil to that found in all other plant seeds. Jojoba seeds accumulate wax esters, rather than triacylglycerols, and waxes have far superior lubricating properties compared with the normal seed oils. Unfortunately, jobaba plants only grow in American deserts, which precludes their use in European agriculture. To circumvent this problem, we propose to transfer the genes for wax biosynthesis from jojoba (and other organisms which make wax esters) to suitable plant species for evaluation and testing. It is proposed to use Arabidopsis as a model system to identify the best combination of genes to make waxes with the most useful properties, and having determined these, introduce them into a dedicated industrial oilseed crop, Brassica carinata (Ethiopian mustard). Importantly, by using a crop species that is not used to produce food, this will ensure that our waxes (to serve as biolubricants) will not enter the human food chain. Overall, this project aims to demonstrate the feasablity of substituting plant-derived wax esters for petrochemically-derived lubricants, providing a new green, sustainable source of these important compounds.