STUDIES ON CALICHEAMICIN BIOSYNTHESIS AND SELF RESISTANCE

加利车霉素生物合成及自身抗性研究

• 批准号: 8248288
• 负责人: Jon Scott Thorson
• 金额: $ 28.01万
• 依托单位: UNIVERSITY OF KENTUCKY
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-05-01 至 2014-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8248288
• 关键词: Address; Alkylation; Anabolism; Anthraquinones; Architecture; Biochemical; Biological; Biological Factors; Chemicals; Chemistry; Clinical; Cloning; Complex; Coupled; Crystallization; DNA; DNA Binding Domain; Development; Dynemicin; Enzymes; Escherichia coli; Evaluation; Fermentation; Gene Cluster; Gene Proteins; Gene Silencing; Genetic; Goals; In Vitro; Lead; Libraries; Molecular; Participant; Phase; Production; Proteins; Recombinants; Resistance; Resources; Role; Sensory; Series; Solubility; Specificity; Structure; Sulfur; analog; assay development; catalyst; glycosylation; glycosyltransferase; in vitro Assay; in vivo; novel; oxidation; programs; protein expression; public health relevance; research study; structural biology; structural genomics; sugar; sugar nucleotide; thiosugar; tool

DESCRIPTION (provided by applicant): Natural products (NPs) and NP derivatives are an unrivaled, but highly under-represented, resource. Arguably among the most notable natural products discovered to date, the 10-membered enediynes - exemplified by the saccharide-fused calicheamicins (CLM) and the anthraquinone-fused dynemicins (DYN) - offer unprecedented molecular architecture, spectacular biological activity and demonstrated clinical utility. The objective of the first phase of this study (CA84374, years 1-4) was to i) clone and characterize the CLM gene cluster from M. echinospora, ii) develop the genetic tools to address CLM biosynthesis in M. echinospora, iii) investigate the mechanism(s) of CLM self-resistance, and iv) initiate aryltetrasaccharide biosynthetic studies. With these goals largely achieved and new tools/information in place, the second phase of this program (CA84374, years 5-9) was focused upon i) cloning and characterization of the DYN gene cluster from M. chersina, ii) development of genetic tools to address DYN biosynthesis in M. chersina, iii) initiating enediyne core biosynthetic studies, iv) structurally characterization of the CLM self-sacrifice resistance protein CalC, and v) the elucidation of key aryltetrasaccharide biosynthetic transformations (sugar N-oxidation, thiosugar formation and GT-catalyzed aryltetrasaccharide assembly). The successful completion of the majority of phase II aims enables the proposed course of study for this competitive renewal. Specifically, we will focus upon i) extending our understanding of enediyne core biosynthesis, ii) delineating the potential role of CalC in regulating CLM production in M. echinospora, iii) completing the study of key aryltetrasaccharide sugar nucleotide transformations (sulfur installation and sequential C-C alkylation of the N-alkyl dideoxypentose), iv) initiating an enediyne structural biology program and v) synthesizing and evaluating (neo)glycorandomized libraries of CLM and DYN. PUBLIC HEALTH RELEVANCE: This is a second competitive renewal of a productive program ((CA84374) targeting the biosynthesis of 10-membered enediynes (calicheamicin and dynemicin) - a novel class of anticancer natural products. The program is anticipated to provide pioneering discoveries in enzyme-catalyzed chemistries, new tools for the chemical diversification of complex natural products and unique anticancer lead compounds.

描述（由申请人提供）：天然产物 (NP) 和 NP 衍生物是一种无与伦比的资源，但代表性极低。 10 元烯二炔可以说是迄今为止发现的最著名的天然产物之一，以糖融合的加利车霉素 (CLM) 和蒽醌融合的动力霉素 (DYN) 为代表，提供了前所未有的分子结构、惊人的生物活性和经证实的临床实用性。本研究第一阶段（CA84374，第 1-4 年）的目标是 i) 克隆并表征棘孢分枝杆菌的 CLM 基因簇，ii) 开发解决棘孢分枝杆菌中 CLM 生物合成问题的遗传工具，iii)研究 CLM 自身抵抗的机制，以及 iv) 启动芳基四糖生物合成研究。随着这些目标的基本实现和新工具/信息的到位，该计划的第二阶段（CA84374，第 5-9 年）重点关注 i) 来自 M. chersina 的 DYN 基因簇的克隆和表征，ii) 遗传基因的开发解决 M. chersina 中 DYN 生物合成的工具，iii) 启动烯二炔核心生物合成研究，iv) CLM 的结构表征自我牺牲抗性蛋白 CalC，以及 v) 关键芳基四糖生物合成转化的阐明（糖 N 氧化、硫代糖形成和 GT 催化的芳基四糖组装）。第二阶段大部分目标的成功完成使得本次竞争性更新的拟议学习课程得以实现。具体来说，我们将重点关注 i) 扩展我们对烯二炔核心生物合成的理解，ii) 描述 CalC 在调节棘孢分枝杆菌 CLM 生产中的潜在作用，iii) 完成关键芳基四糖糖核苷酸转化（硫安装和顺序 C-C）的研究N-烷基双脱氧戊糖的烷基化），iv）启动烯二炔结构生物学计划和 v）合成和评估CLM 和 DYN 的（新）糖随机化文库。 公共健康相关性：这是一项富有成效的计划（（CA84374）的第二次竞争性更新，目标是生物合成 10 元烯二炔（加利刹霉素和动力霉素）——一类新型抗癌天然产物。该计划预计将在酶方面提供开创性的发现-催化化学、复杂天然产物化学多样化的新工具和独特的抗癌先导化合物。