Engineering oilseeds to synthesise designer wax esters

蜡是一种具有有用特性的脂类，特别是作为润滑剂。现代工业世界依赖于数百万台机器和工艺的平稳运行，所有这些都需要润滑剂来减少摩擦和磨损。目前，大多数润滑油是由原油通过化学转化制成的，这一过程消耗了这种正在减少的自然资源，既作为原料，又作为驱动反应的能源。换句话说，石油化工衍生的润滑油是不可持续的。虽然植物种子产生油，但这些作为润滑剂不是很有效，因为它们容易氧化，使它们变粘。然而，一种特殊的植物，荷荷巴，使一个不同的类油，在所有其他植物种子中发现。荷荷巴种子积累蜡酯，而不是三酰基甘油，蜡具有比普通种子油更优越的上级润滑性能。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。为了解决这个问题，我们建议将霍霍巴蜡生物合成的基因（以及其他产生蜡酯的生物）转移到合适的植物物种中进行评估和测试。建议使用拟南芥作为模型系统来鉴定基因的最佳组合以制造具有最有用特性的蜡，并且在确定了这些特性之后，将它们引入专用的工业油籽作物埃塞俄比亚芥（Brassica carinata）（埃塞俄比亚芥菜）中。重要的是，通过使用不用于生产食物的作物物种，这将确保我们的蜡（用作生物润滑剂）不会进入人类食物链。总的来说，该项目旨在证明用植物来源的蜡酯替代石化来源的润滑剂的可行性，为这些重要化合物提供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.