ObjectivesThe spread of antibiotic resistant bacteria is an important threat for human health. Acinetobacter baumannii bacteria impose such a major issue, as multidrug- to pandrug-resistant strains have been isolated, rendering some infections untreatable. In this context, carbapenem-resistant A. baumannii bacteria were ranked as top priority by both WHO and CDC. In addition, A. baumannii bacteria survive in harsh environments, being capable of resisting to disinfectants and to persist prolonged periods of desiccation. Due to the high degree of variability found in A. baumannii isolates, the search for new antibacterials is very challenging because of the requirement of drug target conservation amongst the different strains. Here, we screened a chemical library to identify compounds active against several reference strains and carbapenem-resistant A. baumannii bacteria.
MethodsA repurposing drug screen was undertaken to identify A. baumannii growth inhibitors. One hit was further characterized by determining the IC50 and testing the activity on 43 modern clinical A. baumannii isolates, amongst which 40 are carbapenem-resistant.
ResultsThe repurposing screen led to the identification of a harmine-derived compound, called HDC1, which proves to have bactericidal activity on the multidrug-resistant AB5075-VUB reference strain with an IC50 of 48.23 µM. In addition, HDC1 impairs growth of 43 clinical A. baumannii isolates.
ConclusionsWe identified a compound with inhibitory activity on all tested strains, including carbapenem-resistant clinical A. baumannii isolates.
目的:抗生素耐药细菌的传播对人类健康构成重要威胁。鲍曼不动杆菌是一个主要问题,因为已经分离出多重耐药和泛耐药菌株,使得一些感染无法治疗。在这种情况下,对碳青霉烯耐药的鲍曼不动杆菌被世界卫生组织和疾病控制中心列为首要问题。此外,鲍曼不动杆菌能够在恶劣环境中存活,能够抵抗消毒剂并持续干燥长时间。由于鲍曼不动杆菌分离物中发现的高度可变性,寻找新的抗菌剂非常具有挑战性,因为需要在不同菌株之间保持药物靶点的一致性。在这里,我们筛选了一个化学药物库,以识别对多个参考菌株和碳青霉烯耐药的鲍曼不动杆菌具有活性的化合物。
方法:进行重新利用药物筛选,以识别鲍曼不动杆菌生长抑制剂。其中一个命中物进一步通过确定IC50并测试对43个现代临床鲍曼不动杆菌分离物的活性进行表征,其中40个是碳青霉烯耐药的。
结果:重新利用药物筛选导致发现了一种名为HDC1的Harmine衍生物化合物,其对多重耐药AB5075-VUB参考菌株具有细菌杀灭活性,IC50为48.23微米。此外,HDC1还抑制了43个临床鲍曼不动杆菌分离物的生长。
结论:我们发现了一种对所有测试菌株具有抑制活性的化合物,包括碳青霉烯耐药的临床鲍曼不动杆菌分离物。