Biosynthesis of Fungal Natural Products on Collaborating Iterative Polyketide Synthases

协作迭代聚酮化合物合成酶上真菌天然产物的生物合成

• 批准号: 0948751
• 负责人: Istvan Molnar
• 金额: $ 58.04万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-03-01 至 2016-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0948751&HistoricalAwards=false
• 关键词: Biosynthesis; Fungal; Natural; Products; Collaborating

Polyketides are one of the largest families of natural products with an astonishing structural variety and a remarkable range of biological activities. Polyketides are biosynthesized in fungi by polyketide synthase (PKS) multienzymes whose individual enzymatic domains are used repeatedly. While only a single PKS multienzyme is sufficient to produce most fungal polyketides, some of these natural products are assembled by two collaborating fungal PKSs. Such collaborations represent significant departures from the canonical biosynthetic logic of fungal polyketide biosynthesis. The overarching goal of the current project is to clarify the presently unknown molecular mechanistic details of the assembly of polyketides on such collaborating PKSs, using the biosynthesis of resorcylic acid lactones (RAL) and the related dihydroxybenzeneacetic acid lactones (DAL) as models. Specifically, the project aims to: 1: Characterize the biosynthesis of dehydrocurvularin, a DAL-type natural product; 2: Express RAL and DAL polyketide synthetases, their appropriate mutants, and hybrid enzymes in alternative microbial hosts, and evaluate the production of polyketides using these enzymes and synthetic substrates; and 3: Demonstrate combinatorial biosynthesis by combining related biosynthetic pathways. These experiments will clarify the programming rules that dictate the assembly of polyketides from simpler metabolites, and control the final shape (cyclization patterns) of such natural products. The lessons learned will advance our understanding of iterative enzymatic catalysis, and contribute to the development of combinatorial biosynthetic methods for the production of "designer" polyketides that may be used as novel agrochemicals or high value specialty chemicals in the future.Broader ImpactsEqually important, the project will incorporate training, education and outreach activities. Extensive research-based training opportunities will be provided to graduate and undergraduate students, including those from minority and underrepresented groups. The project will also train community college undergraduate student interns, and may host high school seniors as interns under the auspices of a successful outreach program of the University of Arizona. All students will learn the interdisciplinary science of microbial metabolite biosynthesis and the practice of combinatorial biosynthesis, thus preparing them for careers in the biotechnology industry and in academic research. Further, professional development opportunities will also be provided to K-12 educators to learn about natural products and their biosynthesis by microorganisms: this knowledge may later be integrated into their science curricula.This project is jointly supported by the Metabolic Biochemistry Program of the Division of Molecular and Cellular Biosciences and the Chemistry of Life Processes Program in the Chemistry Division.

聚酮类化合物是天然产物中最大的家族之一，具有惊人的结构多样性和广泛的生物活性。在真菌中，聚酮类化合物是由聚酮合成酶(PKS)多酶合成的，这些酶的各个酶切域被重复使用。虽然只有一个PKS多酶足以产生大多数真菌多酮，但这些天然产物中的一些是由两个协作的真菌PKS组装而成的。这种合作代表着与真菌聚酮生物合成的典型生物合成逻辑的重大背离。本项目的总体目标是以间苯二酸内酯(Ral)和相关的二羟基苯乙酸内酯(DAL)的生物合成为模型，阐明目前未知的聚酮在这种协作的PKS上组装的分子机制细节。具体地说，该项目的目标是：1：表征DAL类天然产物脱氢弯曲素的生物合成；2：在替代微生物宿主中表达Ral和DAL聚酮合成酶及其适当的突变体和杂交酶，并评估使用这些酶和合成底物生产多酮的情况；以及3：结合相关的生物合成途径展示组合生物合成。这些实验将阐明从较简单的代谢物中组装聚酮的编程规则，并控制此类天然产品的最终形状(环化模式)。所学到的经验将促进我们对迭代酶催化的理解，并有助于开发组合生物合成方法来生产未来可能用作新型农用化学品或高价值特种化学品的“设计型”聚酮。广泛影响同样重要的是，该项目将包括培训、教育和推广活动。将向研究生和本科生，包括来自少数群体和代表性不足群体的学生，提供广泛的研究型培训机会。该项目还将培训社区大学本科生实习生，并可能在亚利桑那大学一个成功的外联计划的赞助下，接待高三学生作为实习生。所有学生将学习微生物代谢物生物合成的跨学科科学和组合生物合成的实践，从而为他们在生物技术行业和学术研究中的职业生涯做好准备。此外，还将为K-12教育工作者提供专业发展机会，以了解天然产品及其微生物的生物合成：这些知识稍后可能被整合到他们的科学课程中。该项目由分子和细胞生物科学部的新陈代谢生物化学计划和化学部的生命过程化学计划共同支持。