Dithiolopyrrolone Antibiotics: Biosynthesis, Mode of Action and Cellular Function

二硫代吡咯酮抗生素：生物合成、作用方式和细胞功能

基本信息

批准号：
8720018
负责人：
Bo Li
金额：
$ 24.81万
依托单位：
UNIV OF NORTH CAROLINA CHAPEL HILL
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-03-01 至 2016-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8720018
关键词：
Accounting Affect Affinity Affinity Labels Anabolism Animal Model Antibiotics Antineoplastic Agents Bacteria Biochemical Pathway Biochemistry Bioinformatics Biological Factors Biological Process Cancer cell line Cell physiology Chemicals Chemistry Communicable Diseases Coupled DNA DNA-Directed RNA Polymerase Data Development Disulfides Engineering Environment Enzymatic Biochemistry Enzymes Escherichia coli Exhibits Family Flavins Foundations Future Gene Cluster Gene Expression Genes Genetic Genome Homologous Gene Human In Vitro Individual Investigation Label Learning Light Logic Malignant Neoplasms Mentors Methods Microbial Genetics Microbiology Mining Modeling Molecular Target Nature Organism Oxidation-Reduction Oxidative Stress Pathway interactions Pharmaceutical Preparations Pharmacologic Substance Phase Physiological Post-Translational Protein Processing Production Proteomics RNA chemical synthesis Radio Regulation Regulator Genes Research Role Signal Transduction Signaling Molecule Streptomyces Structure Structure-Activity Relationship Systems Biology Testing Therapeutic Thinking Training Work affinity labeling analog antimicrobial base biological adaptation to stress design enzyme mechanism experience follow-up fungus genetic manipulation improved in vivo insight medical schools member microorganism novel novel therapeutics oxidation promoter research study scaffold skills synthetic enzyme tool

项目摘要

Project Summary Dithiolopyrrolone antibiotics share a unique disulfide-bridged heterobicyclic core and exhibit potent activities against bacteria, fungi, and mammalian cancer cell lines. Although the dithiolopyrrolones have been known for over sixty years, their therapeutic mode of action, biosynthesis, and physiological functions are not well understood. A genome-mining approach was used to identify the biosynthetic gene cluster of a particular dithiolopyrrolone compound, holomycin, in its producing strain, Streptomyces clavuligerus. This preliminary work established the foundation for more intensive investigations of the dithiolopyrrolone scaffold, described herein. This proposal includes three specific aims: 1) Elucidating the modes of action of dithiolopyrrolones including holomycin. Holomycin is hypothesized to exert its activity through redox cycling and/or protein modification. A systems biology approach will be undertaken to group holomycin with antibiotics with known mechanisms of action. In conjunction, transcriptional profiling studies of holomycin-treated bacteria will be carried out to further provide clues regarding the mode of action. Pull down experiments will also be performed in bacterial culture to identify the molecular target(s) and chemical reactivity of holomycin; 2) Investigating the biosynthetic pathway of dithiolopyrrolones. In-depth characterization of the order and mechanisms of individual enzymatic transformations will be carried out regarding the holomycin biosynthetic pathway, in particular the redox chemistry involved in the oxidation steps and bicyclic ring formation. Further, a genome-mining approach will be utilized to uncover unknown dithiolopyrrolone gene clusters and novel dithiolopyrrolone compounds; 3) Scrutinizing the functions and regulatory mechanisms of holomycin in Streptomyces. Though identified as antibiotics and anticancer molecules, dithiolopyrrolones are hypothesized to serve as signaling molecules for their producing organisms. Transcriptional profiling studies will be undertaken to examine the effects of holomycin in S. clavuligerus and model Streptomyces strain, S. coelicolor. The regulatory mechanism of holomycin production will be explored through transcriptional analysis and genetic manipulation of the regulatory genes present in the cluster. The studies described in this proposal will significantly advance our understanding of Nature's logic to assemble dithiolopyrrolones and their mechanisms of action, provide new ways to convert them into viable therapeutics for cancer and infectious diseases, and shed light on the intricate regulatory network of secondary metabolites in Streptomyces, the industrial workhorses accounting for a large number of drugs in current use.

项目摘要二硫代吡咯酮抗生素具有独特的二硫键桥梁杂环核和展览针对细菌，真菌和哺乳动物癌细胞系的有效活性。虽然二硫代吡咯酮已有六十年以上，他们的治疗方式，生物合成和生理功能尚不清楚。一种基因组挖掘方法用于鉴定特定二硫代吡咯酮化合物的生物合成基因簇，全霉素在其产生的菌株中，链霉菌链球菌。这项初步工作已建立描述的二硫醇吡咯酮支架的更深入研究的基础在此处。该建议包括三个具体目的：1）阐明二硫代吡咯酮，包括全霉素。假设全霉素通过氧化还原循环和/或蛋白质修饰。系统生物学方法将采取与抗生素具有已知作用机理的抗生素组。结合将进行全霉素处理细菌的转录分析研究，以进一步提供有关行动方式的线索。下拉实验也将在细菌中进行培养以鉴定雄霉素的分子靶标和化学反应性； 2）调查二硫代吡咯酮的生物合成途径。订单的深入表征和关于型全霉素，将进行单个酶转化的机制生物合成途径，特别是氧化步骤中涉及的氧化还原化学和双环环形成。此外，将利用一种基因组挖掘方法来发现未知的二硫代吡咯基因簇和新型二硫代吡咯酮化合物； 3）仔细检查链霉菌中全霉素的功能和调节机制。尽管被确定为假设抗生素和抗癌分子，二硫代吡咯酮作为信号传导分子生产生物。转录分析研究将进行检查全霉素在链球菌和模型链霉菌菌株中的作用，S。 Coelicolor。全霉素产生的调节机制将通过群集中存在的调节基因的转录分析和遗传操纵。该提案中描述的研究将大大提高我们对自然的理解组装二硫代吡咯龙及其作用机理的逻辑，提供了新的方法将它们转化为可为癌症和传染病的可行疗法，并阐明链霉菌，工业主力的二级代谢产物的复杂调节网络在当前使用中考虑了大量药物。