Heteroresistance Interdisciplinary Research Unit (Project 2)

异阻性跨学科研究单元（项目2）

• 批准号: 10583505
• 负责人: DAVID S WEISS
• 金额: $ 55.09万
• 依托单位: EMORY UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-03-05 至 2026-02-28
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10583505
• 关键词: Acinetobacter baumannii; Affect; Antibiotic Resistance; Antibiotics; Bacteria; Bacterial Infections; Biology; Cells; Cessation of life; Citric Acid Cycle; Classification; Clinic; Clinical; Clinical Trials; Complement; Confusion; Diffusion; Enterobacter; Enterobacteriaceae; Europe; Exhibits; Formulation; Fosfomycin; Foundations; Gene Amplification; Genetic; Glucose; Glutamates; Glutathione; Guidelines; Heterogeneity; Infection; Interdisciplinary Study; Intermediate resistance; Intervention; Intravenous; Life; Malignant Neoplasms; Mediating; Medical; Metabolic; Modeling; Modern Medicine; Mus; Mutation; Operative Surgical Procedures; Oral; Pathway interactions; Patients; Pharmaceutical Preparations; Phenotype; Population; Predisposition; Prevalence; Prevalence Study; Process; Repression; Research Project Grants; Resistance; Risk; Role; Safety; Shunt Device; Signal Transduction; Testing; Time; Transplantation; Treatment Failure; Treatment outcome; Urinary tract infection; Work; alpha ketoglutarate; antibiotic resistant infections; bacterial resistance; carbapenem-resistant Enterobacteriaceae; chemotherapy; clinical diagnostics; combat; design; drug development; experimental study; human disease; improved; in vivo; insight; member; metabolomics; mortality; non-genetic; novel; novel strategies; novel therapeutics; pathogen; resistance mechanism; sugar; surveillance data

ABSTRACT Antibiotic resistance is one of the most serious medical challenges of our time. This crisis puts patients at risk of untreatable bacterial infections and threatens major advances of modern medicine that rely on antibiotics (transplants, chemotherapy, etc). There are at least 2.8 million antibiotic resistant infections each year in the US, leading to over 35,000 deaths [1]. Without significant action, worldwide annual mortality due to these infections is predicted to reach 10 million by 2050, surpassing that predicted for cancer [2]. Understanding resistance mechanisms is critical to designing novel approaches and therapeutics to combat resistant bacteria. Heteroresistance (HR) is an enigmatic form of antibiotic resistance in which a bacterial isolate harbors a resistant subpopulation that can rapidly replicate in the presence of an antibiotic, while a susceptible subpopulation is killed [3, 4]. We have observed HR to the antibiotic, fosfomycin, which is a member of its own drug class and has primarily been used in the US in an oral form to treat urinary tract infections (UTIs) [5]. The use of fosfomycin has recently increased as bacteria become resistant to other classes of drugs [6] and due to its strong safety profile. Due to its increased need and expected expanded approval for IV use, fosfomycin is expected to become a much more prominent part of the antibiotic arsenal in the US. Therefore, it is essential that we elucidate the biology of fosfomycin resistance to guide clinical use. Strikingly, our surveillance data revealed that the rate of fosfomycin HR among carbapenem-resistant Enterobacteriaceae (CRE; 72%) and Acinetobacter baumannii (CRAB; 89%) was higher than that of any other antibiotic tested, and that a large proportion was not detected by clinical diagnostics [7]. We recently demonstrated that HR to diverse antibiotics, including fosfomycin, can cause treatment failure in vivo [4]. Interestingly, and thus far unique among studied examples of HR, we found that fosfomycin HR is caused by two distinct, co-existing resistant subpopulations, both of which replicate in the presence of drug and are not persisters, but form resistant small (R-SM) or large (R-LG) colonies. Results from a transposon screen and metabolomic experiments revealed the underlying basis for the R-SM and R-LG cells to be metabolic heterogeneity, rather than unstable genetic changes such as gene amplification. We will dissect how metabolic signaling drives the expansion of the resistant R-SM subpopulation and the roles of glutamate and glutathione in this process. We will then study the prevalence of distinct fosfomycin resistant subpopulations among diverse clinical isolates. This work will have a sustained and powerful impact on our understanding of non- genetic mechanisms of HR and metabolic and phenotypic heterogeneity. This will complement Project 1 which focuses on unstable genetic mechanisms of HR. The new and fundamental insights gained will lay the foundation for the discovery of novel therapeutics and interventions targeting subpopulations to reduce human disease.

抽象的 抗生素耐药性是我们这个时代最严重的医疗挑战之一。这场危机使患者处于危险之中 不可治疗的细菌感染并威胁依赖抗生素的现代医学的重大进展 （移植，化学疗法等）。每年至少有280万个抗生素耐药感染 美国，导致超过35,000人死亡[1]。没有重大行动，全球每年死亡率由于这些 预计到2050年，预计感染将达到1000万，超过预测的癌症[2]。理解 耐药机制对于设计新颖的方法和治疗剂来对抗抗性细菌至关重要。 杂种（HR）是一种神秘的抗生素耐药性形式，其中细菌分离物具有A 在存在抗生素的情况下可以快速复制的抗性亚群，而易感性 亚群被杀死[3，4]。我们已经观察到抗生素Fosfymycin的HR，该霉素是其本身的成员 药物类别，主要在美国以口服形式用于治疗尿路感染（UTI）[5]。这 由于细菌对其他类型的药物具有抗性[6]，因此Fosfomycin的使用最近增加了 其强大的安全性。由于其需求增加并预期扩大了IV使用的认可， 预计Fosfomycin将成为美国抗生素武器库中更为突出的部分。 因此，至关重要的是，我们必须阐明Fosfomycin耐药性的生物学以指导临床使用。 令人惊讶的是，我们的监视数据表明，抗碳青霉烯的Fosfomycin HR速率 肠杆菌科（CRE; 72％）和鲍曼尼（Baumannii）（螃蟹； 89％）高于其他任何人 抗生素测试了，临床诊断未检测到很大一部分[7]。我们最近 证明包括fosfomycin在内的多种抗生素的人力资源会在体内导致治疗衰竭[4]。 有趣的是，到目前为止，在研究的HR例子中，我们发现Fosfomycin HR是由 两个不同的，共存的抗性亚群，两者在存在药物的情况下复制，不是 坚持不懈，但形成抗性小（R-SM）或大（R-LG）菌落。从转座子屏幕和 代谢组实验揭示了R-SM和R-LG细胞的基础是代谢 异质性，而不是遗传变化，例如基因扩增。我们将剖析新陈代谢 信号传导驱动抗性R-SM亚群的扩展以及谷氨酸和谷胱甘肽的作用 在此过程中。然后，我们将研究在不同的Fosfomycin抗性亚群中的流行率 不同的临床分离株。这项工作将对我们对非 - 的理解产生持续和强大的影响 人力资源和代谢和表型异质性的遗传机制。这将补充项目1 专注于人力资源的不稳定遗传机制。获得的新的和基本的见解将为 发现针对亚群的新型治疗和干预措施的基础 减少人类疾病。