Artemisinin Biosynthesis: IPP Source of Carbon

青蒿素生物合成：IPP 碳源

• 批准号: 6702193
• 负责人: PAMELA J WEATHERS
• 金额: $ 19.26万
• 依托单位: WORCESTER POLYTECHNIC INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-04-01 至 2007-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6702193
• 关键词: antimalarial agents; antineoplastics; biosynthesis; carbon; diene; gene expression; high performance liquid chromatography; lactones; medicinal plants; messenger RNA; northern blottings; nuclear magnetic resonance spectroscopy; plant extracts; polymerase chain reaction; root; sesquiterpenes; terpenes

DESCRIPTION (provided by applicant): Artemisinin (AN), a sesquiterpene lactone, and its derivatives are proven, effective antimalarial therapeutics that also show anticancer activity. However, the complex compound is still best produced in plants; and the drug is in short supply. AN can be produced in transformed root cultures of Artemisa annua L.; we have considerable experience with controlling production. Since to our knowledge it has not yet been established which of the two arms of the terpenoid biosynthetic pathway are operational in the biosynthesis of artemisinin, we hypothesize that AN is produced from a pool of IPP that originates from both the mevalonate and the non-mevalonate pathway, as shown for sesquiterpenes of chamomile, a close relative of Artemisia annua L. Since the sesquiterpene cyclase, ADS, leads to AN and has recently been, we hypothesize that this gene is also present and responsive in our transformed roots that are known producers of artemisinin. Objectives: to be accomplished over 2.5 years (% effort): 1. To do C13 labeling experiments to determine the fate of carbon in artemisinin biosynthesis so that we might know whether one, the other, or both arms of the terpenoid biosynthetic pathway are playing a role in its production. (65%) 2. To produce a molecular probe for the specific sesquiterpene cyclase (SQC) gene, amorpha-4,11-diene synthase (ADS), that leads to artemisinin in order to study any future ADS expression in hairy roots if roots ire ever to be considered as a production system for artemisinin. (15%) 3. To demonstrate that expression of the ADS probe correlates with artemisinin production using conditions where production is known to be either very high or very low. (20%) The long-term goal of our work is to improve fundamental understanding of the regulatory control of terpene production in hairy roots so that we can demonstrate their utility as a production system for important secondary metabolites. This study will enhance our understanding of the biosynthesis of AN in plants and further our ability to increase production of artemisinin while improving overall understanding of terpenoid biosynthesis.

说明(申请人提供)：青蒿素(AN)，一种倍半萜内酯，及其衍生物已被证明是有效的抗疟疾治疗药物，也显示出抗癌活性。然而，这种复杂的化合物最好还是在植物中生产；而且这种药物供不应求。转化的黄花蒿根培养物可以产生AN，我们在控制产量方面有相当的经验。由于据我们所知，尚未确定萜类生物合成途径的两个臂中的哪一个在青蒿素的生物合成中起作用，我们假设AN是由来自甲戊酸和非甲戊酸途径的IPP产生的，就像洋甘菊的倍半萜一样，甘菊是青蒿素的近亲。由于倍半萜环化酶ADS导致AN，并且最近是，我们假设这个基因也存在于我们的转化根中并具有响应性，这些转化根是已知的青蒿素产生者。 目标：在2.5年内完成(努力的百分比)： 1.进行C13标记实验，以确定碳在青蒿素生物合成中的去向，从而了解萜类生物合成途径的一条、另一条或两条臂是否在其合成过程中发挥作用。(65%) 2.针对导致青蒿素的倍半萜环化酶(SQC)基因紫穗菊-4，11-二烯合成酶(ADS)制备分子探针，以研究ADS在毛状根中的表达是否被认为是青蒿素的生产系统。(15%) 3.在已知青蒿素产量很高或很低的情况下，证明ADS探针的表达与青蒿素产量相关。(20%) 我们工作的长期目标是提高对毛状根中萜类产生的调控的基本了解，以便我们能够证明它们作为重要次生代谢物的生产系统的有效性。这项研究将加深我们对植物中AN生物合成的了解，并进一步提高我们增加青蒿素产量的能力，同时提高对萜类化合物生物合成的整体理解。