Antimicrobial-resistant (AMR) infections pose a serious risk to human and animal health. A major factor contributing to this global crisis is the sharing of resistance genes between different bacteria via plasmids. The WHO lists Enterobacteriaceae, such as Escherichia coli and Klebsiella pneumoniae, producing extended-spectrum β-lactamases (ESBL) and carbapenemases as "critical" priorities for new drug development. These resistance genes are most often shared via plasmid transfer. However, finding methods to prevent resistance gene sharing has been hampered by the lack of screening systems for medium-/high-throughput approaches. Here, we have used an ESBL-producing plasmid, pCT, and a carbapenemase-producing plasmid, pKpQIL, in two different Gram-negative bacteria, E. coli and K. pneumoniae Using these critical resistance-pathogen combinations, we developed an assay using fluorescent proteins, flow cytometry, and confocal microscopy to assess plasmid transmission inhibition within bacterial populations in a medium-throughput manner. Three compounds with some reports of antiplasmid properties were tested; chlorpromazine reduced transmission of both plasmids and linoleic acid reduced transmission of pCT. We screened the Prestwick library of over 1,200 FDA-approved drugs/compounds. From this, we found two nucleoside analogue drugs used to treat HIV, abacavir and azidothymidine (AZT), which reduced plasmid transmission (AZT, e.g., at 0.25 μg/ml reduced pCT transmission in E. coli by 83.3% and pKpQIL transmission in K. pneumoniae by 80.8% compared to untreated controls). Plasmid transmission was reduced by concentrations of the drugs which are below peak serum concentrations and are achievable in the gastrointestinal tract. These drugs could be used to decolonize humans, animals, or the environment from AMR plasmids.IMPORTANCE More and more bacterial infections are becoming resistant to antibiotics. This has made treatment of many infections very difficult. One of the reasons this is such a large problem is that bacteria are able to share their genetic material with other bacteria, and these shared genes often include resistance to a variety of antibiotics, including some of our drugs of last resort. We are addressing this problem by using a fluorescence-based system to search for drugs that will stop bacteria from sharing resistance genes. We uncovered a new role for two drugs used to treat HIV and show that they are able to prevent the sharing of two different types of resistance genes in two unique bacterial strains. This work lays the foundation for future work to reduce the prevalence of resistant infections.

中文翻译：

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HIV药物抑制携带广谱β-内酰胺酶和碳青霉烯酶基因的质粒的转移。


抗生素耐药性 (AMR) 感染对人类和动物健康构成严重风险。造成这场全球危机的一个主要因素是不同细菌之间通过质粒共享耐药基因。世界卫生组织将产生超广谱 β-内酰胺酶 (ESBL) 和碳青霉烯酶的肠杆菌科细菌（例如大肠杆菌和肺炎克雷伯菌）列为新药开发的“关键”优先事项。这些抗性基因最常通过质粒转移共享。然而，由于缺乏中/高通量方法的筛选系统，寻找防止抗性基因共享的方法受到了阻碍。在这里，我们在两种不同的革兰氏阴性细菌大肠杆菌和肺炎克雷伯氏菌中使用了产生 ESBL 的质粒 pCT 和产生碳青霉烯酶的质粒 pKpQIL。荧光蛋白、流式细胞术和共聚焦显微镜以中等通量的方式评估细菌群体内的质粒传输抑制。测试了三种具有抗质粒特性报道的化合物；氯丙嗪减少了两种质粒的传播，亚油酸减少了 pCT 的传播。我们筛选了包含 1,200 多种 FDA 批准的药物/化合物的 Prestwick 库。由此，我们发现了两种用于治疗 HIV 的核苷类似物药物，阿巴卡韦和叠氮胸苷 (AZT)，它们可减少质粒传播（AZT，例如，0.25 μg/ml 时，可将大肠杆菌中的 pCT 传播减少 83.3%，将 K 中的 pKpQIL 传播减少与未经治疗的对照组相比，肺炎球菌感染率降低了 80.8%）。药物浓度低于峰值血清浓度并且可在胃肠道中实现，从而减少了质粒传播。 这些药物可用于消除人类、动物或环境中的 AMR 质粒。 重要性 越来越多的细菌感染对抗生素产生耐药性。这使得许多感染的治疗变得非常困难。这是一个如此大的问题的原因之一是细菌能够与其他细菌共享它们的遗传物质，而这些共享的基因通常包括对多种抗生素的耐药性，包括我们的一些最后手段。我们正在通过使用基于荧光的系统来寻找能够阻止细菌共享耐药基因的药物来解决这个问题。我们发现了两种用于治疗艾滋病毒的药物的新作用，并表明它们能够防止两种独特的细菌菌株共享两种不同类型的耐药基因。这项工作为未来减少耐药感染流行的工作奠定了基础。