Mycoprotein 2.0

随着经济的繁荣，对肉类的需求也随之增加，因为肉类是蛋白质的丰富来源。这反过来又增加了对水资源的需求，改变了土地利用（在某种程度上高度依赖于如何喂养动物），并导致人为温室气体排放的增加。许多国际机构认为这是不可持续的，一些机构估计，到2050年，温室气体排放总量将从目前的11%上升到70%。然而，对蛋白质的需求也可以通过基于作物的来源（例如大豆和豆类）和真菌蛋白来满足。真菌蛋白是通过将作物来源的葡萄糖发酵成生物质而产生的，然后收获并加工成高质量的蛋白质。在世界范围内，真菌蛋白仍然是一种开发相对不足的资源，但它为全年生产高质量蛋白质提供了巨大的希望，而高质量蛋白质是未来粮食安全和人类营养的重要需求。生产中最重大的挑战是对单一碳源的依赖，一种小麦衍生的葡萄糖，在适合使用之前需要特殊处理。我们最近的工作表明，虽然用于生产真菌蛋白的真菌生长在这种葡萄糖底物上，但许多必需维生素的生产受到抑制。我们最近的工作揭示了维生素在一些其他碳源中的表达，例如甜菜衍生蔗糖糖浆。在某些情况下，但不是所有情况下，这与其他有害次生代谢物的增加有关。这就引出了一个问题，真菌是如何调节与碳源相关的次级代谢的？为了扩大真菌蛋白的营养价值和可利用的碳源范围（使生产能够转移到世界其他地区），我们将使用最新的DNA测序技术来揭示镰刀菌的基因组结构，并研究包含次级代谢物基因的基因组区域。从对其他相关真菌的研究中，我们知道次生代谢（SM）的控制是由SM簇在基因组中的位置和特定的调节因子调控的。利用最新的测序技术将使我们能够定位解决SM的位置，并确定调节对不同碳源的反应的潜在机制。通过一系列可控批次和连续培养实验，我们将开发出在不诱导有害SM基因表达的情况下，在一系列碳源中选择性诱导维生素生物合成的技术，为SM的控制提供理解，并为未来的产品开发提供增强产品。在我们现有工作的基础上，我们将扩大分子技术工具箱，以编辑线虫的基因组，去除有害的次生代谢物基因簇及其在不同碳源诱导下的调控因子。作为这项工作的结果，将能够利用更广泛的英国农业来源（玉米、大麦、大米），利用更广泛的碳源来生产真菌蛋白，甚至转向以蔗糖为基础的真菌蛋白生产（目前完全无法获得的碳源），利用英国的蔗糖来源，如甜菜。此外，增强真菌蛋白中微量营养素补充的能力将扩大其作为全球饮食重要组成部分的用途，并为肉类提供更可持续和更灵活的替代品。

As prosperity rises, demand for meat increases as it is a rich source of protein. This in turn places demand on water resources, changes land use (in a manner highly dependent upon how the animal is fed) and leads to an increase in anthropogenic GHG emissions. This has been determined to be unsustainable by a number of international bodies, with some estimates predicting a 70% rise from current levels of 11% of total GHG emissions by 2050. However, demand for protein can also be met by crop-based sources (e.g. soy and pulses) and by mycoprotein, produced by fermentation of crop-derived glucose into biomass, which is harvested and processed into high quality protein. Mycoprotein remains a relatively under-exploited resource worldwide but offers great promise for year-round production of high quality protein, a vital requirement for future food security and human nutrition. The most significant challenge to production is the reliance on a single carbon source, a wheat-derived glucose, which requires special processing before it is suitable for use. Our recent work has revealed that while the fungus used to produce mycoprotein is grown on this glucose substrate, production of a number of essential vitamins is inhibited. Our recent work has revealed that expression of vitamins in some other carbon sources, for example beet derived sucrose syrup is observed. In some, but not all cases, this is coupled to an increase in other deleterious secondary metabolites. This leads to the question, how is the fungus regulating secondary metabolism in relation to carbon source? To expand both the nutritional value of mycoprotein and the range of carbon sources that can be utilised (enabling production to move to other regions of the world) we will use the latest DNA sequencing techniques to reveal the structure of the genome of Fusarium venenatum and study the regions of the genome that contain secondary metabolite genes. From work carried out in other related fungi it is known that control of secondary metabolism (SM) is regulated by the position of SM cluster in the genome, and by specific regulatory factors. Utilising the latest sequencing techniques will allow us to positionally resolve SM location and determine the underlying mechanisms regulating responses to different carbon sources.Through a series of controlled batch and continuous culture experiments we will develop techniques to selectively induce vitamin biosynthesis across a range of carbon sources, without inducing the expression of deleterious SM genes, providing both an understanding of the control of SM and an enhanced product for future product development. Building on our existing work we will expand the toolbox of molecular techniques in order to edit the genome of F. venenatum to remove deleterious secondary metabolite gene clusters and their regulatory factors which are induced in response to different carbon sources. As a result of this work, mycoprotein will be able to be produced using a larger range of carbon sources drawing upon a wider range of UK agricultural sources (maize, barley, rice) and even shift to sucrose-based production of mycoprotein (a carbon source that has currently been completely inaccessible), utilising UK sources of sucrose such as sugar beet. Furthermore, the ability to enhance the complement of micronutrients in mycoprotein will broaden its utility as an important component of global diets and offers a more sustainable and flexible alternative to meat.