CAREER: A multidisciplinary approach to the investigation of secondary metabolism in nematodes

佛罗里达大学的丽贝卡·a·布彻博士正在研究不同种类的线虫（蛔虫）用来控制其发育的化学信号。该奖项由化学学部生命过程化学项目资助。线虫种类繁多（超过25,000种特征物种），可以寄生，在植物和动物（包括人类）中引起广泛的疾病。尽管线虫的影响巨大，但令人惊讶的是，人们对这类重要生物的化学信号知之甚少。对线虫所使用的化学信号的化学结构和生物合成的研究将有助于开发新的化学工具和策略来干扰它们的生命周期和生存，从而提供新的治疗选择。该奖项还促进了本科生从植物内部微生物中分离天然产物的发现基础实验课程的发展。在这门课程中，学生从植物中分离内生菌，从这些内生菌中提取提取物，并筛选提取物的抗线虫活性。该奖项旨在描述线虫用来控制其发育的关键小分子信号的化学结构。利用野生型线虫和生物合成突变体之间的比较代谢组学，可以鉴定具有代表性的线虫物种的小分子信号。然后使用质量导向分馏纯化相关化合物，并使用核磁共振光谱对其结构进行表征。通过比较不同线虫物种的化学结构和生物合成基因序列，可以绘制出特定酶结构域在线虫进化过程中的作用。为了研究特定酶结构域的活性，本研究采用了多学科方法，结合了生物化学、有机化学、结构生物学、分析化学和线虫遗传学等工具。该奖项的结果有望揭示线虫如何控制其生命周期，并开发新的方法来减少寄生线虫的生存。这个项目的教育部分通过开发一个基于发现的（而不是烹饪书式的）天然产品鉴定实验课程来增加本科生在科学领域的保留率。该课程为本科生和高中生提供了研究机会，并可能导致发现具有抗线虫活性的新型细菌/真菌代谢物。

With this award, funded by the Chemistry of Life Processes Program in the Chemistry Division, Dr. Rebecca A. Butcher of the University of Florida is investigating the chemical signals used by different species of nematodes (roundworms) to control their development. Nematodes are very diverse (over 25,000 characterized species) and can be parasitic, causing widespread disease in plants and animals (including humans). Despite the huge impact of nematodes, surprisingly little is known about chemical signaling in members of this important class of organisms. Investigations into the chemical structures and biosynthesis of the chemical signals used by nematodes should enable the development of new chemical tools and strategies to interfere with their life cycles and survival and thus provide new treatment options. This award also promotes the development a discovery-based laboratory course for undergraduates in the isolation of natural products from microorganisms that live inside plants. In this course, students isolate endophytes from plants, generate extracts from these endophytes, and screen the extracts for anti-nematode activities. This award aims to characterize the chemical structures of key small-molecule signals that nematodes use to control their development. The small-molecule signals from representative nematode species can be identified using comparative metabolomics between wild-type worms and biosynthetic mutants. The relevant compounds are then be purified using mass-guided fractionation, and their structures characterized using NMR spectroscopy. Comparison of the chemical structures and biosynthetic gene sequences from different nematode species enables the roles of specific enzymatic domains to be mapped across nematode evolution. To study the activities of specific enzymatic domains, this study uses a multidisciplinary approach incorporating tools from biochemistry, organic chemistry, structural biology, analytical chemistry, and nematode genetics. The results of this award are expected to shed light on how nematodes control their life cycles and the development of novel methods to reduce the survival of parasitic nematodes. The educational portion of this project increases retention of undergraduate students in science fields by developing a discovery-based (rather than cookbook style) laboratory course in natural product identification. The proposed course extends the research opportunities for undergraduate and high school students and may lead to the discovery of novel bacterial/fungal metabolites with anti-nematode activities.