Bioprospecting antibiotics in the fungal secondary metabolome

描述(申请人提供)：尽管抗生素取得了显著的成功，但细菌性疾病仍然是全球第二大死亡原因，导致全球1700万人死亡。在感染疾病的背景下，最重要的公共卫生问题之一是在抗生素治疗期间持续和迅速地出现抗药性细菌。因此，不可否认，迫切需要开发新的抗菌疗法来对抗多重耐药感染。事实上，抗药性的速度已经超过了新抗菌剂的发现，产生了对具有新作用机制的新抗生素的迫切需求。天然产品在抗生素化疗中发挥了重要作用，从1941年的青霉素开始，在接下来的几十年里，又出现了一系列其他值得信赖的药物。仅在过去的25年里，天然产品就激发了75%以上的小分子抗生素，并且在过去的40年里，仅批准了三种新的抗生素类别中的两种。然而，一个主要的担忧是，基于天然产品预测新的先导剂正变得越来越困难。这在很大程度上被认为是由于对现有生产有机体的全面挖掘，以及对它们的代谢途径的相对完整的了解。然而，人们也普遍预测，环境微生物产生的化合物的财富和可获得性实际上被严重低估，这在很大程度上是因为许多生物合成途径在实验室生长条件下是沉默的。在这项研究中，我们建议采用一种新颖但有先例的方法，从表观遗传上修改海洋边缘内生真菌的独特文库，以触发潜在和隐蔽代谢物的产生。这些微生物非常适合在这样的项目中使用，因为它们几乎完全没有在抗菌药物发现的背景下开发，同时 同时具有固有的复杂的次生代谢体。因此，我们寻求通过表观遗传操作来解锁真菌分离株中休眠的代谢途径，以开发具有抗菌活性的新的次生代谢物。这将通过以下几个方面来实现：1。天然产物先导化合物的生产、纯化和结构分析。这一目标将为筛选内生真菌提供化学多样性，这些内生真菌既可以用表观遗传修饰剂培养，也可以不用表观遗传修饰剂培养。从这些培养物中提取的抗菌提取物将被分离、纯化并确定其结构。保持良好生物活性的新型化学类型将进一步表征：2.先导剂的综合活性和毒性图谱。为此，我们将对LED制剂进行优先和合理的分析，确定它们对多重耐药ESKAPE病原体的抗菌谱，它们对真核细胞的细胞毒性作用，它们的抗生物被膜特性，以及细菌对它们的作用的耐药性。我们认为，我们的初步工作；再加上新的方法，使我们的项目有很高的机会为未来的抗生素开发产生新的和新的化学支架。

DESCRIPTION (provided by applicant): Despite the notable success of antibiotics, bacterial diseases remain the second-leading cause of mortality worldwide, causing 17 million deaths globally. One of the most significant public health concerns in the context of infectious disease is the continued and rapid emergence of drug resistant bacteria during antibiotic treatment. As such, there is an undeniable and desperate need to develop new antibacterial therapeutics to fight multi-drug resistant infections. Indeed, the pace of drug resistance has outstripped the discovery of new antimicrobial agents, creating an urgent need for new antibiotics with novel mechanisms of action. Natural products have played a major role in antibiotic chemotherapy, beginning with penicillin in 1941, and followed by a litany of other trusted agents over the ensuing decades. In the last twenty-five years alone, natural products have inspired more than 75% of small molecule antibiotics, and two of only three new antibiotic classes approved in the last forty years. A major concern, however, is that natural product based divining for new lead agents is becoming increasingly difficult. This is largely believed to result from the comprehensive mining of available producing organisms, and a relatively complete understanding of their metabolic pathways. However, it is also widely projected that the wealth and availability of compounds produced by environmental microorganisms has actually been sorely underestimated, in large part because many biosynthetic pathways are silent under laboratory growth conditions. In this study, we propose to take the novel, but precedented, approach of epigenetically modifying a unique library of marine-margin endophytic fungi to trigger production of latent and cryptic metabolites. These organisms are ideal for use in such a project as they are almost entirely untapped in the context of antibacterial drug discovery, whilst at the same time possessing inherently complex secondary metabolomes. As such, we seek to unlock dormant metabolic pathways in our fungal isolates via epigenetic manipulation, for the exploitation of new secondary metabolites that possess antibacterial activity. This will be achieved by: 1. The production, purification and structural analysis of natural product lead compounds. This aim will provide chemodiversity for screening, derived from endophytic fungi cultivated both with and without epigenetic modifiers. Antibacterial extracts derived from these cultures will be isolated, purified and their structures determined. Novel chemotypes retaining favorable bioactivity will then further characterized by: 2. A comprehensive activity and toxicity profiling of lead agents. In this aim we will perform a prioritized and rationalized analysis of led agents by determining their antibacterial spectrum of activity against multi-drug resistant ESKAPE pathogens, their cytotoxic effects towards eukaryotic cells, their anti-biofilm properties, and the potential for bacterial resistance to their effects. We contend that our preliminary work; coupled with novel approaches, give our project a very high chance of yielding new and novel chemical scaffolds for future antibiotic development.