Plasmid Eviction to Restore Susceptibility in Carbapenem-Resistant Enterobacteriaceae

质粒驱逐可恢复耐碳青霉烯类肠杆菌科细菌的敏感性

基本信息

批准号：
8954519
负责人：
JAMES E KIRBY
金额：
$ 13.05万
依托单位：
BETH ISRAEL DEACONESS MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-07-01 至 2017-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8954519
关键词：
Anti-Infective Agents Antibiotic Resistance Antibiotics Bacterial Chromosomes Biological Assay Blood Carbapenems Centers for Disease Control and Prevention (U.S.)Chromosomes Collection DNA Development Drug resistance Enterobacteriaceae Infections Eukaryotic Cell Genome Goals Growth Human In Vitro Infection Label Learning Maintenance Maximum Tolerated Dose Measures Metabolic Modeling Multi-Drug Resistance Mus Operon Output Performance Pharmaceutical Preparations Phase Plasmids Pneumonia Predisposition Property Proteins Relative (related person)Reporter Reporter Genes Resistance Signal Transduction Specificity Structure-Activity Relationship Technology Testing Therapeutic Therapeutic Effect Thigh structure Tissues Validation analog antimicrobial base carbapenem resistance carbapenem-resistant Enterobacteriaceae carbapenemase clinically relevant combat drug resistant bacteria high throughput screening in vitro Assay in vivo in vivo Model inhibitor/antagonist mouse model novel pathogen public health relevance research study resistance gene screening small molecule

项目摘要

DESCRIPTION (provided by applicant): Carbapenem-resistant Enterobacteriaceae are an emerging class of multi-drug resistant bacterial pathogens that are either effectively untreatable or only treatable with toxic antimicrobials. Their resistance to carbapenems is especially problematic, as these agents are often the last line of defense against drug- resistant pathogens. Therefore, the CDC now categorizes such carbapenem-resistant Enterobacteriaceae (CRE) in their top antibiotic resistance threat level. New anti-infective strategies are urgently needed. Carbapenemase genes (and resistance to many other antimicrobials) are carried on large, low copy number plasmids. An underlying hypothesis of this proposal is that it should be possible to target these plasmids for "eviction", thereby restoring carbapenem susceptibility to these strains. Considered more broadly, this strategy might also be employed to restore susceptibility to many other antimicrobials as well. Therefore, proof of principle is sought for combating carbapenem resistance through plasmid eviction therapy. To accomplish this goal, in the R21 phase, a screening strategy will be developed, validated, and implemented to identify small molecule inhibitors of plasmid maintenance. The screening strategy is based on technology that will allow quantitative assessment of plasmid loss. Specifically, novel transposons will be used to integrate reporter genes into the carbapenemase resistance plasmid and bacterial chromosome of a screening strain, thereby providing an easily measured readout of normalized plasmid number. A mid-size high throughput screen for anti-plasmid agents will then be used to identify potent inhibitors of plasmid maintenance. The inhibitors will be tested for their ability to restore carbapenem susceptibility, i.e., adjunctive antimicrobial activity. In the R33 phase, a larger high throughput screen will be performed to identify additional potent anti-plasmid agents appropriate for further development. Iterative structure-activity relationship studies will then be used to identify analogues with enhanced pharmacological potential. Finally, the activity of select anti-plasmid agents will be characterize in murine infection models to establish in vivo efficacy. Taken together, these experiments should establish the theoretical basis for this adjunctive antimicrobial therapy and its potential use as a new human therapeutic.

描述（由适用提供）：耐碳青苯肠杆菌科是一类新兴的多药耐药细菌病原体，它们实际上是无法治疗的，或者只能用有毒的抗菌剂治疗。它们对碳青霉烯的抵抗力尤其有问题，因为这些药物通常是对耐药病原体的最后防御。因此，CDC现在将这种抗碳青霉烯抗杆菌科（CRE）分类为顶级抗生素耐药性威胁水平。迫切需要新的反感染策略。碳青霉酶基因（以及对许多其他抗菌剂的耐药性）都在大的低拷贝数质粒上携带。该提议的一个基本假设是，应该有可能将这些质粒靶向“驱逐”，从而恢复碳青霉烯对这些菌株的敏感性。更广泛地认为，该策略也可以用于恢复对许多其他抗菌剂的易感性。因此，寻求原理证明来通过质粒工程疗法对抗碳青霉苯甲酸的耐药性。为了实现这一目标，在R21阶段，将制定，验证和实施筛选策略，以识别质粒维持的小分子抑制剂。筛选策略基于将允许对质粒损失进行定量评估的技术。具体而言，新型的转座子将用于将报道基因的基因整合到筛选菌株的碳纤维酶抗性质粒和细菌染色体中，从而提供了易于测量的归一化质粒数量的读数。然后，将使用抗质粒药物的中型高吞吐量屏幕来鉴定质粒维持的潜在抑制剂。抑制剂将测试其恢复碳青霉烯敏感性的能力，即辅助性抗菌活性。在R33阶段，将执行较大的高吞吐量屏幕，以确定适合进一步开发的其他潜在抗质粒剂。然后，将使用迭代结构 - 活性研究研究来识别具有增强药物潜力的类似物。最后，在鼠类感染模型中，将表征精选的抗质粒药物的活性以建立体内效率。综上所述，这些实验应为这种辅助抗菌治疗及其作为新的人类治疗的潜在用途建立理论基础。