Metals, Drugs and Fungal Pathogens

项目总结/摘要 白色念珠菌通常是一种无害的微生物，但它可以机会性地侵入 血液中的免疫功能低下的人，并迅速蔓延到多个器官，从而引起生命- 威胁真菌感染有限的抗真菌药物库，耐药念珠菌的流行 菌株，以及在了解真菌细胞如何适应成为病原体方面的重大差距是严重的威胁 对人类健康的影响。这里提出的研究探讨了创新和未探索的概念， 在感染过程中营养金属的可利用性以目前不可预测的方式影响药物功效。在 同时，真菌对药物胁迫的反应影响真菌如何重塑其金属生物学以抵抗药物， 行动和有利于毒力。这一假设是基于申请人实验室收集的初步数据 表明白色念珠菌生长培养基中铜的量显著调节了 三种不同类型的抗真菌剂的效力和耐药性：过渡金属离子载体，唑类， 抗菌肽这些研究与申请人开发化学工具的长期目标一致， 操纵生物金属离子位置、形态和反应性以获得潜在的治疗益处。整体 本申请的目的是鉴定赋予金属调节的免疫调节的靶点、机制和途径。 对与人类健康相关的真菌物种的药物效力的反应。这一目标将通过使用 化学、遗传和蛋白质组学方法的有力结合，以解决三个具体目标：1） 确定细胞生长环境中的金属可用性如何影响真菌的表型结果 用常见的唑类药物治疗的病原体; 2）确定金属可用性如何调节细胞 抗真菌药物应激反应; 3）确定金属调节的抗真菌药物应激反应的分子和生物学决定因素。 抗真菌组胺素肽的杀念珠菌活性。这些目标将利用生长介质 严格控制金属浓度，将白色念珠菌的药物敏感性与 在生长抑制、形态学和总细胞金属含量方面的可测量结果。第二和第三 aims使用有针对性和无偏见的功能基因组学和金属蛋白质组学方法来识别基因 和金属蛋白，其影响唑类或组蛋白的处理或受唑类或组蛋白的处理的影响， 可变金属水平。由世界领先的真菌致病机理专家组成的合作团队， 金属生物学加上令人信服的初步结果表明，这些战略的可行性， 申请人。这些研究对于了解金属状态如何影响抗真菌药物疗效的影响将 为克服耐药性和开发新的抗菌策略提供新的方向， 考虑到宿主-病原体界面上复杂的金属生物学沿着。

PROJECT SUMMARY/ABSTRACT Candida albicans is usually a harmless commensal organism, but it can opportunistically invade the bloodstream of immunocompromised individuals and quickly spread to multiple organs, giving rise to life- threatening fungal infections. The limited arsenal of antifungal drugs, the prevalence of drug-resistant Candida strains, and significant gaps in understanding how fungal cells adapt to become pathogenic are serious threats to human health. The research proposed here explores the innovative and unexplored concept that changes in nutrient metal availability over the course of infection affect drug efficacy in currently unpredictable ways. At the same time, fungal responses to drug stress influence how fungi remodel their metallobiology to resist drug action and favor virulence. This hypothesis is based on preliminary data collected in the applicant's laboratory showing that the amount of copper in the growth medium of Candida albicans dramatically modulates the potency and resistance of three different classes of antifungal agents: transition metal ionophores, azoles, and antimicrobial peptides. These studies align with the applicant's long-term goals to develop chemical tools to manipulate biological metal ion location, speciation, and reactivity for potential therapeutic benefit. The overall objective of the current application is to identify targets, mechanisms, and pathways that confer metal-adjusted responses in drug efficacy against fungal species relevant to human health. This objective will be met by using a powerful combination of chemical, genetic and proteomic approaches to address three specific aims: 1) Determine how metal availability in the cellular growth environment affects phenotypic outcomes of fungal pathogens treated with common azole drugs; 2) Determine how metal availability modulates the cellular response to antifungal drug stress; and 3) Identify molecular and biological determinants of metal-modulated candidacidal activity of the antifungal histatin peptides. These aims will take advantage of growth media rigorously controlled for metal concentrations to correlate drug susceptibility of Candida albicans with measurable outcomes in growth inhibition, morphology and total cellular metal content. The second and third aims use both targeted and unbiased functional genomic and metalloproteomic approaches to identify genes and metalloproteins that influence or are influenced by treatment with azoles or histatins under conditions of variable metal levels. The assembled collaborative team of world-leading experts in fungal pathogenesis and metallobiology coupled with compelling preliminary results demonstrate feasibility of these strategies by the applicant. The impact of these studies for understanding how metal status affects antifungal drug efficacy will inform new directions for overcoming drug resistance and developing new antimicrobial strategies that take into account complex metallobiology along the host-pathogen interface.