The Chemistry of Fungal Antagonism and Defense

该项目的重点是对真菌寄生/真菌的化学研究，这些真菌攻击和定居由自然界中其他真菌产生的长期生理结构(例如，基质和其他子实体)。核心的基本假设是，真菌的侵袭通常涉及对宿主的抗生素，因此，这样的殖民者可能是宝贵的、未被开发的天然抗真菌药物的来源。到目前为止，从北部森林栖息地(伊利诺伊州/威斯康星州)、亚热带纬度(佐治亚州/佛罗里达州)和夏威夷岛上发现的不同小气候中收集的600多个基质和多孔菌标本中分离出了2300多种细菌。这些收集包含相当大的生物多样性，包括许多新的或相对未被探索的类群的代表，以及已知的真菌寄生物种。化学研究将重点放在夏威夷收藏中尚未探索的活跃线索上。第二个目标是发现广为传播的玉米内生真菌玉米顶孢子菌的分离物通常会产生一系列耐人寻味的天然产物(吡咯菌素)。这些发现导致了对代表各种分类群的大约200个玉米内生真菌分离物集合的探索，以寻找其他显示出对真菌竞争对手的拮抗作用的新的真菌代谢物。有了这个奖项，有机和高分子化学计划再次支持爱荷华大学化学系詹姆斯·B·格洛尔教授的工作。Gloer教授和他的合作者，美国农业部的Patrick F.Dowd和Donald T.Wicklow正在从真菌中分离出新的有机化合物，这些研究的指导思想是一个假设，即寄生真菌可能是新化学结构的丰富来源，因为它们需要对宿主进行化学控制。通过对真菌培养物的研究，发现了许多新的生物活性天然产物。这一独特的、不断增长的工作最终将使将宿主、地理和气候与生物和化学多样性联系起来的努力成为可能。由此产生的数据可能被证明对指导未来来源的选择很有用。抗真菌药物在农业和医学方面对社会具有潜在的实用价值，也可以作为工具来帮助发现新的作用模式。该项目的研究成果还有望有助于其他学科的基础科学知识，包括真菌生态学、分类学、生物多样性、作物/食品科学和进化生物学。

The project focuses on chemical studies of mycoparasitic/fungicolous fungi that attack and colonize long-lived physiological structures (e.g., stromata and other fruit bodies) produced by other fungi in nature. The central underlying hypothesis is that invasion by fungal colonists often involves antibiosis toward the host, and therefore, such colonists may be valuable, underexplored sources of natural antifungal agents. Thus far, over 2,300 cultures have been isolated from over 600 specimens of stromata and polypores collected from northern forested habitats (Illinois/Wisconsin), subtropical latitudes (Georgia/Florida), and diverse microclimates found on the island of Hawaii. These collections contain considerable biodiversity, and include representatives of many new or relatively unexplored taxa, as well as known mycoparasitic species. Chemical studies will focus on as-yet unexplored active leads from the Hawaiian collection. A second objective follows from the discovery that isolates of the widespread corn endophyte Acremonium zeae commonly produce a set of intriguing natural products (pyrrocidines). These findings have led to the initiation of exploration of a collection of ca. 200 corn endophyte isolates, representing a variety of taxa, in search of other new fungal metabolites that show antagonistic effects against fungal competitors.With this award, the Organic and Macromolecular Chemistry Program is renewing support for the work of Professor James B. Gloer, of the Department of Chemistry at the University of Iowa. With his collaborators, Patrick F. Dowd and Donald T. Wicklow, of the U.S. Department of Agriculture, Professor Gloer is isolating new organic compounds from fungi, with these studies guided by a hypothesis that parasitic fungi may be rich sources of new chemical structures given their need to develop chemical control over their hosts. Many new bioactive natural products have been discovered through studies of fungal cultures. This unique, growing body of work will ultimately enable efforts to correlate host, geography, and climate with biological and chemical diversity. The resulting data could prove useful in guiding future selection of sources. Antifungal agents are of potential practical value to society in agriculture and medicine, and can also be valuable as tools to assist in discovery of new modes of action. Findings from this project are also expected to contribute to fundamental scientific knowledge in other disciplines, including fungal ecology, taxonomy, biodiversity, crop/food science, and evolutionary biology.