Antimicrobial discovery from metabolomics of nematode pathogen interactions

描述(申请人提供)：医药和农业对抗生素的广泛依赖导致抗生素耐药性的持续出现，引发了抗生素时代结束的幽灵。这场危机突显了确定新的抗生素和抗感染战略的必要性。我们的研究计划专注于探索尚未开发的潜在抗菌剂-我们假设线虫在具有高度复杂微生物群落特征的栖息地使用的化合物，以对抗细菌和真菌，包括堆肥土壤、腐烂的水果和腐烂的昆虫身体。我们的建议汇集了秀丽线虫先天免疫和宿主-微生物相互作用(D.K.)领域以及线虫代谢组学和小分子信号转导领域(F.S.)高度互补的专业知识。我们将集中于线虫物种的代谢组学分析，这两种线虫以细菌为食，在自然环境中暴露于各种非致病和致病细菌和真菌中，但它们对细菌的敏感性也存在差异。我们最近对这些线虫代谢物的研究发现了几类新的功能尚未确定的小分子，它们的化学结构暗示着与细菌的相互作用。我们建议开发线虫代谢物库，以丰富这些线虫宿主对病原菌和真菌产生的化合物，包括人类病原体铜绿假单胞菌和金黄色葡萄球菌。然后，我们将筛选这些小分子代谢物库的抗微生物活性，利用已建立的跟随线虫宿主的微生物增殖和存活的致病分析，随后通过比较代谢组学和化学合成最终鉴定活性化合物。我们期待找到直接影响细菌和真菌活性的化合物，以及通过调节微生物定植和 毒力机制。我们的项目有可能识别新类别的抗微生物化合物和潜在的新的抗感染机制，这些机制可能有助于遏制抗生素耐药微生物的浪潮。

DESCRIPTION (provided by applicant): The widespread dependence on antibiotics in medicine and agriculture have resulted in the continued emergence of antibiotic resistance, raising the specter of the end of the antibiotic era. This crisis has underscored the need for the identification of new antibiotics and anti-infective strategies. Our research proposal focuses on the exploration of an untapped potential reservoir of antimicrobials-compounds that we hypothesize nematodes employ as chemical defense against bacteria and fungi, in habitats characterized by highly complex microbiomes, including compost soil, rotting fruit, and decomposing insect carcasses. Our proposal brings together the highly complementary expertise from the field of Caenorhabditis elegans innate immunity and host-microbe interactions (D.K.), and from the field of C. elegans metabolomics and small- molecule signaling (F.S.). We will focus on metabolomic analysis of the nematode species C. elegans and Pristionchus pacificus, each of which feed on bacteria and are exposed to a wide variety of non-pathogenic and pathogenic bacteria and fungi in their natural environments, but which also exhibit differences in susceptibility to bacteria. Our recent studies of the metabolomes of these nematodes have identified several novel classes of small molecules of yet undetermined function that have chemical structures suggestive of interactions with bacteria. We propose to develop nematode metabolite libraries that are enriched for compounds produced by these nematode hosts in response to pathogenic bacteria and fungi, including the human pathogens Pseudomonas aeruginosa and Staphylococcus aureus. We will then screen these small molecule metabolite libraries for antimicrobial activity, taking advantage of established pathogenesis assays that follow microbial proliferation and survival of the nematode host, with subsequent definitive identification of active compounds via comparative metabolomics, and chemical synthesis. We anticipate finding compounds that directly affect bacterial and fungal viability as well as metabolites that function through the modulation of microbial colonization and virulence mechanisms. Our project has the potential to identify new classes of antimicrobial compounds and potentially novel anti-infective mechanisms that may help stem the tide of antibiotic resistant organisms.