Role of ribosome modulating proteins in conferring Mycobacterium abscessus antibiotic resistance

核糖体调节蛋白在赋予脓肿分枝杆菌抗生素耐药性中的作用

基本信息

批准号：
10094343
负责人：
Pallavi Ghosh
金额：
$ 50.03万
依托单位：
WADSWORTH CENTER
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-09-21 至 2025-08-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10094343
关键词：
Amikacin Aminoglycoside resistance Aminoglycosides Antibiotic Resistance Antibiotic susceptibility Antibiotics Bacteria Binding Binding Proteins Biochemical Cefoxitin Chronic Collaborations Cryoelectron Microscopy Development Dissociation Drug resistance Environment Exhibits Exposure to Genetic Genomics Guanosine Triphosphate Phosphohydrolases Hibernation Imipenem In Vitro Infection Injectable Intervention Lung infections Macrolides Mediating Messenger RNA Microbial Antibiotic Resistance Modeling Molecular Mycobacterium abscessus Mycobacterium smegmatis Mycobacterium tuberculosis Oral Pathogenicity Pathway interactions Patients Pharmaceutical Preparations Population Proteins Regimen Resistance Ribosomes Role Site Skin Tissue Soft Tissue Infections Structure Tissues Treatment Efficacy Work Y protein Zinc Zinc deficiency drug sensitivity in vivo lincosamide lung injury mutant mycobacterial novel novel therapeutic intervention pathogen resistance mechanism response tigecycline

项目摘要

Project Summary: Mycobacterium abscessus (Mab) is a rapidly growing NTM causing skin and soft tissue infections and pulmonary infections in patients with chronic lung damage. It stands apart as one of the most antibiotic resistant microbial species, making its infections incredibly difficult to treat. A combination of an oral macrolide and the aminoglycoside, amikacin, comprises the frontline treatment against Mab. Therapy is prolonged and low cure rates are deplorable. The poor efficacies of these antibiotics result from various mechanisms of intrinsic resistance induced in Mab upon exposure to drugs as well as the host environment. Recently we showed that MabHflX, a conserved ribosome-associated GTPase, is required for macrolide-lincosamide resistance (4). The absence of HflX in a DMs_hflX deletion strain results in an increased population of 70S ribosomes suggesting that HflX is involved in dissociation of ribosomes stalled in the presence of antibiotics. However, the detailed mechanism of HflX-mediated antibiotic resistance, as well as the mechanisms by which antibiotic-bound ribosomal subunits are recycled remain unknown. In another study we demonstrated a role for ARE-ABCF proteins in macrolide/lincosamide resistance. In Aim 1 of this proposal we will use a combination of genetic, biochemical and structural approaches to determine the mechanisms of HflX and ABCF-mediated macrolide-lincosamide resistance. In another independent study, aminoglycoside resistance in zinc-starved M. smegmatis was found to originate from ribosome hibernation, which involves binding of mycobacterial protein Y (MPY). We hypothesize that a low-zinc host environment would similarly result in MPY-dependent ribosome hibernation during Mab infection, and confer resistance to aminoglycosides including amikacin. In Aim 2 of this proposal, we will determine the role of MabMPY in aminoglycoside resistance of which could potentially explain the observed discord between in vitro efficiency and in vivo efficacy of the current treatments (Aim 2). The extreme innate antibiotic resistance of Mab presents a unique opportunity to study the convergence of multiple resistance mechanisms in this pathogen. An in-depth understanding of these various mechanisms is critical in the development of new therapeutic approaches towards treatment of Mab infections.

项目概要：脓肿分枝杆菌 (Mab) 是一种快速生长的 NTM，可引起皮肤和软组织感染以及慢性肺损伤患者的肺部感染。它是最独特的抗生素之一耐药微生物种类，使其感染极其难以治疗。口语的组合大环内酯类药物和氨基糖苷类药物阿米卡星构成了针对 Mab 的一线治疗药物。治疗方法是治愈率长期低下令人遗憾。这些抗生素的疗效不佳是由多种原因造成的。暴露于药物和宿主后 Mab 诱导的内在耐药机制环境。最近我们发现 MabHflX（一种保守的核糖体相关 GTP 酶）是大环内酯-林可酰胺耐药性 (4)。 DMs_hflX 缺失菌株中 HflX 的缺失导致 70S 核糖体数量增加表明 HflX 参与核糖体解离停滞在抗生素存在的情况下。然而，HflX介导的抗生素耐药性的详细机制，如以及抗生素结合核糖体亚基回收的机制仍然未知。在在另一项研究中，我们证明了 ARE-ABCF 蛋白在大环内酯/林可酰胺耐药性中的作用。瞄准在该提案的第 1 条中，我们将结合使用遗传、生化和结构方法来确定 HflX 和 ABCF 介导的大环内酯-林可酰胺耐药机制。在另一项独立研究中，发现缺锌的耻垢分枝杆菌对氨基糖苷类药物产生耐药性起源于核糖体冬眠，涉及分枝杆菌蛋白 Y (MPY) 的结合。我们假设低锌宿主环境同样会导致 MPY 依赖性核糖体 Mab 感染期间的冬眠，并赋予对氨基糖苷类药物（包括阿米卡星）的抗性。目标 2 根据该提案，我们将确定 MabMPY 在氨基糖苷类耐药性中的作用，其可能可能解释目前观察到的体外效率和体内功效之间的不一致治疗（目标 2）。 Mab 极端的先天抗生素耐药性为研究该病原体多种耐药机制的融合。深入了解这些各种机制对于开发新的治疗方法至关重要单克隆抗体感染。