Diversification of rhamnolipids/glycolipids in heterologous lipogenic yeast hosts using synthetic biology

利用合成生物学实现异源脂肪生成酵母宿主中鼠李糖脂/糖脂的多样化

• 批准号: RGPIN-2022-05307
• 负责人: Saleh, Ahmad
• 金额: $ 2.04万
• 依托单位: Université Laval
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=744417
• 关键词: Diversification; rhamnolipids; glycolipids; heterologous; lipogenic

Glycolipids (GLs) are produced by diverse organisms, particularly by yeasts and bacteria. The most prominent GLs are rhamnolipids (RLs) that exist in a diversity of RL congeners and homologs. Although their exact physiological functions are unknown, RLs are thought to be produced as defense or survival mechanisms in response to unfavorable environmental conditions. RLs are considered virulence factors of pathogenic microorganisms like Pseudomonas aeruginosa as they help in the colonization of biotic surfaces of humans and plants. Nonetheless, RLs have interesting antimicrobial, antiparasitic, anticancer, immunomodulatory, anti-adherent as well as surface activities allowing them to find several medical, agricultural, environmental, and industrial applications. It is noteworthy that these activities are vary with variations in RL structures creating thus a diversity of biological and physical activities. This richness in biological and physical activities incited the search for new RLs with potentially novel or more interesting activities. Nonetheless, the discovery of new RLs has slowed down drastically in the last decades because it relied on classical screening of new RL producers isolated from environmental samples. This resulted in the redundant identifications of the same RL-producers that are producing the same RLs molecules. Another problem facing RLs commercialization is their costly production arising mainly from the pathogenic nature of their best producers, like P. aeruginosa which is an opportunistic human pathogen. Such pathogenic nature of RL-producers requires costly biocontainment measures which adds to the net cost of RLs. Under the goal to overproduce structurally diverse RLs in non-pathogenic microbial hosts, we set our short-term objective for program to develop proof-of-concept strategies for the genome-mining based heterologous production of diverse RLs in the non-pathogenic lipogenic yeast host, Yarrowia lipolytica. This involves the design of synthetic metabolic circuits biosynthesizing RLs, building and integrating genetic constructs into Yarrowia lipolytica, and finally testing and identification of produced RLs. This design-build-test synthetic biology cycles will be iteratively repeated until the desired RL congener or homolog is produced. In subsequent discovery grants, we will use these strategies to overproduce interesting RL congener or homologs at satisfactory yields and at low cost. This research program will ultimately result in the low-cost production of a diversity of designer RL molecules associated with interesting biological and physical activities that are useful for many therapeutic, environmental, and industrial applications. It will also result in the production of several original research articles, filing of patents and training of highly qualified professionals at undergraduate and graduate levels who will competently contribute to the rising chemical synthetic biology domain in Canada.

糖脂（GL）由多种生物体产生，特别是由酵母和细菌产生。最突出的GL是存在于多种RL同系物和同系物中的鼠李糖脂（RL）。尽管其确切的生理功能尚不清楚，但RL被认为是响应不利环境条件的防御或生存机制。RL被认为是病原微生物如铜绿假单胞菌的毒力因子，因为它们有助于人类和植物的生物表面的定殖。尽管如此，RL具有令人感兴趣的抗微生物、抗寄生虫、抗癌、免疫调节、抗粘附以及表面活性，使得它们能够找到若干医疗、农业、环境和工业应用。值得注意的是，这些活动随着RL结构的变化而变化，从而产生了多种生物和物理活动。生物和物理活动的丰富性激发了对具有潜在新颖或更有趣活动的新RL的搜索。尽管如此，在过去的几十年里，新的RL的发现已经大大放缓，因为它依赖于从环境样品中分离的新RL生产者的经典筛选。这导致产生相同RL分子的相同RL生产者的冗余鉴定。RL商业化面临的另一个问题是其昂贵的生产，主要是由其最佳生产者的致病性引起的，如铜绿假单胞菌，其是一种机会性人类病原体。RL生产者的这种致病性需要昂贵的生物遏制措施，这增加了RL的净成本。 在非致病性微生物宿主中过度生产结构多样性RL的目标下，我们设定了我们的短期目标，以开发基于基因组挖掘的非致病性产脂酵母宿主Yarrowia lipolytica中异源生产不同RL的概念验证策略。这涉及合成代谢回路的设计，生物合成RL，构建遗传构建体并将其整合到解脂耶氏酵母中，最后测试和鉴定所产生的RL。这种设计-构建-测试合成生物学循环将反复重复，直到产生所需的RL同源物或同系物。在随后的发现资助中，我们将使用这些策略以令人满意的产量和低成本过量生产感兴趣的RL同源物或同系物。 这项研究计划最终将导致低成本生产与有趣的生物和物理活动相关的多种设计师RL分子，这些分子可用于许多治疗，环境和工业应用。它还将导致几个原创研究文章的生产，专利申请和本科和研究生水平的高素质专业人员的培训，他们将为加拿大不断上升的化学合成生物学领域做出贡献。