Biosynthesis and Synthetic Biology of Antibiotic Oligosaccharides

抗生素寡糖的生物合成及合成生物学

基本信息

批准号：
10408814
负责人：
BRIAN O BACHMANN
金额：
$ 45.23万
依托单位：
VANDERBILT UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-06-01 至 2024-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10408814
关键词：
3-hydroxybutanal Acids Active Sites Acylation Address Amalgam Anabolism Animals Antibiotic Resistance Antibiotics Bacterial Infections Binding Binding Sites Biochemical Biological Biological Assay Biological Availability Cations Cells Centers for Disease Control and Prevention (U.S.)Chemicals Clinic Clinical Complex Cryoelectron Microscopy Development Disaccharides Drug resistance Enterobacteriaceae Family Fluorine Formulation Generations Genetic Goals Gram-Positive Bacteria Health Human Hydrogen Bonding In Vitro Knowledge Lactones Methods Methylation Methyltransferase Minor Groove Molecular Conformation Molecular Target Multi-Drug Resistance Natural Products Oligosaccharides Organism Oxidases Pathway interactions Peptides Peptidyltransferase Pharmacology Phase Phase III Clinical Trials Property Proteins Resistance Resistance development Ribosomal Interaction Ribosomal RNA Ribosomes Roentgen Rays Role Site Structure Structure-Activity Relationship System Testing Therapeutic Index Time Toxic effect Translations Variant Withdrawal analog carbon skeleton chemical synthesis clinical application clinical development comparative design drug resistant bacteria genome editing hydroxyl group improved in vivo insight member metabolomics microorganism mutant novel pathogenic bacteria pre-clinical prototype resistant strain scaffold small molecule sugar synthetic biology tool virtual

项目摘要

PROJECT SUMMARY Orthosomycins are a family of potent antibiotic oligosaccharides that target a wide spectrum of gram-positive bacteria, including most antibiotic-resistant strains. It is less appreciated that subsets of orthosomycins also target gram-negative drug-resistant bacteria, including members of the Enterobacteriaceae family, which are ranked as some of the highest threats to human health by the Centers for Disease Control and Prevention. Orthosomycins demonstrate high potency, good bioavailability, and low toxicity in vivo in both animals and humans. The promise of this class was explored preclinically, and through subsequent development of one orthosomycin, everninomicin A (Ziracin). Despite Ziracin’s advancement to phase III clinical trials, unstated pharmacological complications led to a strategic decision to discontinue clinical development of this scaffold in 2000. In the intervening time, no attempts have been made to improve the orthosomycins. We speculate that addressing pharmacological liabilities was complicated due to the unknown reasons for withdrawal, the fragmentary understanding of the everninomicin molecular target, and the challenges inherent in orthosomycin chemical synthesis, which requires at least 130 steps. Recently, the structures of orthosomycins bound in the bacterial ribosome have been solved, revolutionizing our understanding of their molecular target and mechanism of action and creating opportunities to improve ribosome interactions and pharmacological properties via targeted structural changes. Contemporaneously, we developed a set of genetic tools for editing the genome of the producing organisms, as well as advanced the understanding of the biochemical mechanisms and pathways of orthosomycin assembly. We have initiated, but not completed, an exploration of the formation of the interglycosidic orthoester linkages, the formation and attachment of dichloroisoeverninic acid, and the biosynthesis of the eurekanate sugar, unique to orthosomycin antibiotics. This convergence of progress in the understanding of orthosomycin biosynthesis and target identification provides an unprecedented opportunity to address the complications limiting the clinical utility of these molecules by improving their potency and pharmacological properties. To further this goal, our specific aims are to (1) characterize and tune the interactions of orthosomycins with rProtein uL16, (2) investigate h89 and h91 spanning interactions of orthosomycins, and (3) develop access to unnatural orthosomycin analogs with targeted structural changes impacting the rRNA h91 pocket. Premise: In this project, we outline probable origins and solutions to pharmacological liabilities. Leveraging biosynthetic insights, we will generate targeted changes in the scaffolds of orthosomycins using a combined genetic, chemical, and biochemical approach. With these designed variants, we will determine the extent to which structural variations can improve ribosome binding, as well as modify pharmacological properties to remove liabilities and improve the therapeutic index.

项目摘要正霉素是一个潜在的抗生素寡糖家族，其靶向广泛的革兰氏阳性细菌，包括大多数抗生素抗性菌株。不太理解的是，正霉素的子集也靶革兰氏阴性耐药细菌，包括肠杆菌科的成员，被疾病控制和预防中心对人类健康的一些最高威胁。正霉素表现出高效力，良好的生物利用度和在动物和人类。该课程的承诺是临床上探索的，并通过随后的发展。正霉素，雌激素A（Ziracin）。尽管Ziracin在III期临床试验中进步，但未说明药理学并发症导致了战略决定，以中止这种脚手架的临床发展 2000年。在此期间，尚未尝试改善正霉素。我们推测解决药品负债的问题很复杂，因为撤回的原因未知对雌激素分子靶靶靶标的零碎理解以及正霉素固有的挑战化学合成，至少需要130步。最近，已经解决了细菌核糖体中结合的正霉素的结构，革命性我们对他们的分子目标和行动机制的理解，并创造了改善的机会通过靶向结构变化，核糖体相互作用和药物特性。同时，我们开发了一组遗传工具，用于编辑生产生物的基因组，并提高理解正霉素组装的生化机制和途径。我们已经发起了，但是尚未完成，探索了糖层之间的矫形连接的形成，形成和二氯依氨酸的附着和尤里克酸糖的生物合成，正肌霉素独有抗生素。在理解正霉素生物合成和靶标方面的这种进步的融合识别提供了一个前所未有的机会来解决限制临床实用性的并发症这些分子通过提高其效力和药物特性。为了进一步这一目标，我们的具体目的是（1）表征和调整正霉素与Rprotein ul16的相互作用，（2）研究H89 H91跨越正霉素的相互作用，以及（3）与与非天然正霉素类似物的访问有针对性的结构变化影响RRNA H91袋。前提：在这个项目中，我们概述了制药负债的有问题的起源和解决方案。利用生物合成见解，我们将使用合并的原霉素产生靶向变化通过这些设计的变体，我们将确定哪些结构变化可以改善核糖体结合，并将药物特性修改为删除负债并改善治疗指数。