Exploring the physicochemical properties governing compound efflux in Gram-negative bacteria

探索革兰氏阴性菌中控制化合物流出的理化特性

基本信息

批准号：
10387611
负责人：
Rebecca Ulrich
金额：
$ 4.68万
依托单位：
UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-01-16 至 2025-01-15
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10387611
关键词：
Anti-Bacterial Agents Antibiotic Resistance Antibiotics Antimicrobial Resistance Bacterial Infections Basic Science Biological Assay Cells Classification Clinical Collection Coupled Data Set Development Drug Kinetics Engineering Escherichia coli Evaluation Excision FDA approved Gram-Negative Bacteria Guidelines In Vitro Infection Libraries Measures Membrane Modeling Modification Multi-Drug Resistance Mus Natural Products Nitrogen Pathogenicity Predisposition Property Quinolones Research Resistance Running Shapes Side Testing Therapeutic Toxic effect Validation Work base chemical property combat design design and construction drug candidate drug resistant bacteria efficacy evaluation efficacy study efflux pump global health improved in vivo inhibitor innovation insight mouse model novel outcome prediction pathogen prevent random forest small molecule tool trait

项目摘要

Project Summary Multi-drug resistant infections are a major threat to global health and resistance has been observed for every clinically-used antibiotic, even those considered to be the last lines of treatment. Further compounding the antimicrobial resistance crisis is the lack of new antibiotics entering the pipeline, particularly for Gram- negative pathogens which have an impermeable outer membrane, limiting small molecule accumulation, and promiscuous efflux pumps, which can recognize and expel most small molecules from the cell. A basic-science understanding of favorable chemical properties required to enhance compound accumulation and decrease efflux propensity is needed to develop antibacterial candidates with whole-cell activity against Gram-negative pathogens. Initial efforts in the Hergenrother lab have identified the physicochemical traits needed for compound permeation in E. coli and successfully applied these guidelines to convert several Gram-positive only antibiotics to broad-spectrum agents. While this strategy improves Gram-negative antibacterial activity, compound efflux is still detrimental to efficacy and prevents development of these leads into potent antibiotics. It is imperative to understand the physicochemical properties governing compound recognition and efflux to provide a novel design platform to engineer efflux susceptibility out of drug candidates. The objective of this proposal is to identify the parameters that define compound efflux in Gram-negative bacteria and apply these findings to remove efflux liability out of promising antibacterial candidates. Work proposed herein will build upon preliminary studies of the efflux propensity of ~200 compounds utilizing a novel LC-MS/MS-based accumulation (Efflux Propensity EvaLuation (EXPEL)) assay which can detect small changes in efflux susceptibilities irrespective of antibacterial activity and a chemoinformatic model which can accurately classify 50% of compounds as efflux substrates and non-substrates. In Specific Aim 1, additional physicochemical properties determined important for compound efflux by the random forest model will be probed through synthesis of a targeted library of side-by-side comparisons. These compounds will be added to the dataset and iterative cycles of compound synthesis, EXPEL assay, and chemoinformatic model validation will be performed. Utilizing the EXPEL assay and the initial properties identified as correlating to efflux ratios, derivatives of an exciting FabI inhibitor will be explored to identify promising antibacterials with decreased efflux liabilities in Specific Aim 2. The therapeutic potential of these compounds will be explored through toxicity studies, determination of pharmacokinetic profile, and evaluation of efficacy in mouse infection models. Specific Aims 1 and 2 will run concurrently and completion of these studies will significantly impact antibacterial research and remedy attrition points in the antibacterial clinical pipeline.

项目摘要多药耐药感染是对全球健康的主要威胁，并且已经观察到抵抗每种临床中使用的抗生素，即使是被认为是最后的治疗方法的抗生素。进一步的复合抗菌耐药性危机是缺乏进入管道的新抗生素，特别是用于革兰氏阴性病原体具有不可渗透的外膜，限制了小分子的积累，并且混杂的外排泵，可以识别并排出大多数小分子从细胞中。基本科学了解增强复合积累和减少所需的有利化学特性需要倾斜倾向来开发具有全细胞活性的抗菌候选者针对革兰氏阴性病原体。 Hergenrother实验室的初步努力已经确定了所需的理化特征大肠杆菌中的复合渗透，并成功地应用了这些准则以转换几个革兰氏阳性仅对广谱药物的抗生素。虽然该策略改善了革兰氏阴性抗菌活性，但复合外排仍然不利于疗效，并防止这些导致其发展为有效的抗生素。必须了解有关复合识别和排出的理化特性为候选药物提供了一个新颖的设计平台，以设计出毒品的易感性。这个目的建议是确定在革兰氏阴性细菌中定义复合外排的参数并应用这些从有希望的抗菌候选者中消除外排责任的发现。本文提出的工作将基于对〜200种化合物的外排倾向的初步研究利用新型LC-MS/MS的积累（外排倾向评估（Expel））测定法检测出液体敏感性的微小变化，而不论抗菌活性和化学变化模型如何可以准确地将50％的化合物分类为外排基材料和非卵石。在特定的目标1中，随机森林模型对化合物外排的其他物理化学特性确定将通过合成并排比较的目标库来探测。这些化合物将是添加到化合物合成，驱除测定和化学信息学模型的数据集和迭代循环中将执行验证。利用驱除测定和所确定的初始特性与将探索令人兴奋的Fabi抑制剂的外排比，以识别有希望的抗菌物特定目标2中的外排负债降低。将探索这些化合物的治疗潜力通过毒性研究，确定药代动力学特征以及评估小鼠感染的功效型号。具体目标1和2将同时运行，这些研究的完成将显着影响抗菌研究和疗法损耗指向抗菌临床管道中的指向。