Biodiversity and Hydrocarbon Degradation Capacity of Marine Fungi

海洋真菌的生物多样性和碳氢化合物降解能力

• 批准号: RGPIN-2017-04325
• 负责人: Walker, Allison
• 金额: $ 1.89万
• 依托单位: Acadia University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=681384
• 关键词: Biodiversity; Hydrocarbon; Degradation; Capacity; Marine

I am interested in the biodiversity of marine fungi and in their ability to degrade hydrocarbons. I am more specifically interested in the species of fungi that grow naturally in the Bay of Fundy and its fringing saltmarshes (eastern Canada) and the extent to which they have natural resilience to marine oil spills. My lab is approaching this problem by first characterizing the diversity of marine fungi from the water column and coastal sediments using morphological and molecular methods (DNA barcoding). We will then use selective media with marine fuel oil as sole carbon source to isolate potential hydrocarbon-degrading fungi. These experiments will allow us to assess the mass loss of crude oil, and provide proof of metabolism of hydrocarbons (C14 naphthalene degradation to CO2). They will also help determine which marine fungi possess cytochrome P450 monooxygenases (P450s), which fungi use to degrade hydrocarbons. Approaches for identifying and quantifying P450s from novel fungal isolates and environmental samples will include protein identification via liquid chromatography-orbitrap tandem mass spectrometry (LC-MS/MS) and quantification via liquid chromatography-selected reaction monitoring mass spectrometry (LC-SRM). This work will be done in collaboration with Dr. Erin Bertrand (Dalhousie Tier II CRC in Marine Microbial Proteomics). ***Preliminary work in my lab has identified candidate strains from Nova Scotia seawater that allow us to investigate if prior exposure to oil increases oil degradation rates by marine fungi. We also intend to study candidate fungal strains singly and in mixed-species consortia to examine the effects of nutrient supplementation and temperature on oil degradation rates. We will use our proteomics approach to explore interactions between native oil degrading fungi and the existing Bay of Fundy microbial community (inhibition or promotion of degradative enzyme production) under different temperature and nutrient regimes. ***We are characterizing this poorly known component of coastal systems to explore the role that fungi play in the resilience to marine oil spills of the Bay of Fundy ecosystem. My lab is the first to take a molecular ecology approach to understanding the biodiversity and oil degrading capacity of marine fungi. In the process, we will also begin to uncover the evolutionary relationships of marine fungi, improving our reference databases for DNA-based fungal identifications, and training students in cutting edge molecular phylogenetics and proteomics approaches. We expect to describe many new species of fungi as we shed light on marine fungal biodiversity and ecological function in northern coastal ecosystems. My work will have broad implications for remediation of oil spills in coldwater marine ecosystems, and for understanding the evolution of fungal cytochrome P450s.

我对海洋真菌的生物多样性和它们降解碳氢化合物的能力感兴趣。我更感兴趣的是芬迪湾及其周边盐沼(加拿大东部)自然生长的真菌种类，以及它们对海洋石油泄漏的天然适应能力。我的实验室正在研究这个问题，首先使用形态和分子方法(DNA条形码)表征来自水柱和沿海沉积物的海洋真菌的多样性。然后，我们将使用以船用燃料油为唯一碳源的选择性培养基来分离潜在的碳氢化合物降解菌。这些实验将使我们能够评估原油的质量损失，并提供碳氢化合物代谢(C14萘降解为二氧化碳)的证据。他们还将帮助确定哪些海洋真菌拥有细胞色素P450单加氧酶(P450)，哪些真菌用来降解碳氢化合物。从新的真菌分离株和环境样品中鉴定和定量P450的方法将包括通过液相色谱-轨道串联质谱仪(LC-MS/MS)和通过液相色谱-选择反应监测质谱仪(LC-SRM)进行蛋白质鉴定。这项工作将与Erin Bertrand博士(Dalhousie Tier II CRC in Ocean微生物蛋白质组学)合作完成。*我实验室的初步工作已经从新斯科舍省的海水中确定了候选菌株，使我们能够调查之前暴露在石油中是否会增加海洋真菌对石油的降解率。我们还打算单独研究候选真菌菌株和混合物种联盟，以检查营养补充和温度对石油降解率的影响。我们将使用我们的蛋白质组学方法来探索不同温度和营养条件下天然石油降解真菌与芬迪湾现有微生物群落(抑制或促进降解酶产生)之间的相互作用。*我们正在对沿海系统中这一鲜为人知的组成部分进行表征，以探索真菌在芬迪湾生态系统对海洋石油泄漏的弹性中所起的作用。我的实验室是第一个采用分子生态学的方法来了解海洋真菌的生物多样性和石油降解能力的实验室。在这个过程中，我们还将开始揭示海洋真菌的进化关系，完善我们基于DNA的真菌鉴定参考数据库，并培训学生使用尖端分子系统学和蛋白质组学方法。随着我们对北部沿海生态系统中海洋真菌生物多样性和生态功能的了解，我们预计将描述许多新的真菌物种。我的工作将对修复冷水海洋生态系统中的石油泄漏，以及理解真菌细胞色素P450的进化具有广泛的意义。