Exploitation of Fungi for Improved Food Quality

真菌对人类社会的影响已经有几千年了，因为它们既有有益的特性，也有有害的特性。有几种真菌已被驯化以满足人类的需要。这些酵母菌包括用于啤酒和葡萄酒生产或烘焙产品的酿酒酵母菌，以及分别用于亚洲烹饪食品生产和霉菌成熟的蓝色和白色奶酪的米曲霉、罗克福青霉和卡门贝青霉的丝状真菌。此外，真菌已被用作害虫的生物防治剂，一些物种已被用于生产有价值的次生代谢物，包括青霉素和他汀类药物。然而，植物致病性真菌造成严重的作物损失，并可能伴随真菌毒素的产生，对全球粮食安全构成重大威胁。本项目的总体主题是利用真菌生物学和代谢知识来提高食品质量和安全，并在生物技术方面进行后续应用。本项目的目标是在白奶酪霉菌P. camemberti的菌株开发方面取得突破，并了解真菌代谢如何影响食品生产的风味和营养方面。研究的微生物是卡曼伯干酪及其野生近亲卡曼伯干酪，用于生产布里干酪和卡曼伯干酪等霉菌成熟的奶酪，以及其他食品。真菌对赋予味道和质地（由于酶的作用）以及外观很重要。该项目旨在：(1)考虑到现有菌株可能产生霉菌毒素以及对脂肪和盐含量的担忧，通过使用经典和遗传技术开发新菌株，实现突破性的菌株改进。我们将借鉴诺丁汉大学以前和正在进行的有关蓝纹奶酪生产中使用的相关真菌P. roqueforti的专业知识。在这个模型中，分子工具已经被用来诱导自然的性循环，以允许不同菌株的杂交，从而能够产生具有潜在的新颖和理想的味道和代谢活动的重组后代。通过紫外诱变也可以开发新的菌株。预计新菌株将改善食品质量和安全。(2)了解真菌代谢与风味之间的联系。酶的作用对奶酪的霉菌成熟至关重要。然而，camberti脂肪酶和蛋白酶活性的遗传和生化基础及其对代谢的影响尚不清楚。因此，我们将使用分子遗传学和生物信息学方法来表征控制这些酶的基因，并评估是否可以通过传统和转基因方法来操纵真菌，以增加风味和营养价值。工作将包括评估用于菌株修改的CRISPR技术。该研究在与真菌和酶的开发有关的食品和生物技术工业中具有潜在的应用前景。博士学位将提供经典微生物学程序、生化实验、生物信息学/基因组学和分子遗传学实验工作以及相关统计数据分析和计算技能方面的培训。也有可能在大学初创公司“Myconeos.com”实习，该公司与该项目有利害关系。

Fungi have impacted on human societies for millennia due to both their beneficial but also detrimental properties. Several fungi have been domesticated to serve human needs. These include the yeast Saccharomyces cerevisiae, which is used in beer and wine production or in bakery products, and the filamentous fungi Aspergillus oryzae, Penicillium roqueforti and Penicilium camemberti which are used in food production in Asian cuisine and mould-ripened blue and white cheeses, respectively. Additionally, fungi have been used as biological control agents of pests, and several species have been exploited for the production of valuable secondary metabolites including penicillin and statins. However, phytopathogenic fungi cause severe crop losses and can be accompanied by mycotoxin production, posing a major threat to global food security.The present project has the overall theme of exploiting knowledge of fungal biology and metabolism to improve food quality and security, with subsequent applications in biotechnology. This project specifically aims to make breakthroughs in strain development for the white-cheese mould P. camemberti, and to understand how fungal metabolism impacts on flavour and nutritional aspects of food production. The study organisms are P. camemberti and its wild relative P. commune used in the production of mould-ripened cheeses such as Brie and Camembert, as well as other food products. The fungus is important for imparting flavour and texture (due to enzyme action) and also appearance. This project aims to:(1) Enable breakthrough strain improvement by using classical and genetic techniques to develop new strains, given that with current strains there is the possibility of mycotoxin production and concerns over fat and salt levels. We will draw on expertise from previous and ongoing studies at Nottingham with the related fungus P. roqueforti used in blue cheese production. In this model, molecular tools have been used to induce a natural sexual cycle to allow crossing of different strains and therefore enable the generation of recombinant offspring with potentially novel, and desirable, flavours and metabolic activities. New strain development is also possible via UV mutagenesis. It is anticipated that new strains will improve food quality and safety.(2) Understand links between fungal metabolism and flavour. Enzyme action is critical for mould-ripening of cheeses. However, the genetic and biochemical basis of lipase and protease activity and consequent impacts on metabolism are poorly understood in P. camberti. We will therefore use molecular genetic and bioinformatic approaches to characterise the genes controlling these enzymes and assess whether the fungus can be manipulated via classical and GM approaches to increase the flavour and nutritional values. Work will include the assessment of CRISPR technologies for strain modification. The research has potential applications in both the food and biotechnology industries relating to exploitation of fungi and enzymes.The PhD will offer training in classical microbiology procedures, biochemical experimentation, bioinformatic/genomic and molecular-genetic experimental work, and associated statistical data analysis and computing skills. There will also be a possibility of an industrial placement at a University start-up company 'Myconeos.com', who have interests allied to the project.