摘要
旨在探究去甲泽拉木醛与美罗培南对New Delhi Metallo-β-lactamase-1(NDM-1)阳性大肠杆菌的协同抗菌作用。首先通过酶活性抑制试验、分子对接试验确定去甲泽拉木醛对NDM-1蛋白水解活性的抑制作用及机制,其次通过棋盘法-最小抑菌浓度试验、生长曲线试验、药敏试验验证去甲泽拉木醛与碳青霉烯类抗生素美罗培南的协同抑菌作用,进一步通过杀菌曲线试验、活死细菌染色试验、膜完整性试验确定两者的协同杀菌作用,最后通过大蜡螟感染模型验证去甲泽拉木醛与美罗培南的体内治疗效果。结果显示,去甲泽拉木醛能够显著抑制NDM-1的水解活性(IC_(50)=0.32 mg/L),并对美罗培南与NDM-1蛋白的结合产生竞争作用。体外试验表明去甲泽拉木醛与美罗培南有良好的协同抗菌作用,并可通过增加美罗培南对细菌的膜损伤作用发挥协同杀菌作用;体内试验表明去甲泽拉木醛可将美罗培南的保护效果从67%提高至80%。本研究为治疗NDM-1阳性大肠杆菌感染提供了一种治疗策略和抗菌增效剂。
This study aims to investigate the synergistic antimicrobial effect of demethylzeylasteral meropenem against NDM-1-positive Escherichia coli.Firstly,the nitrocefin hydrolysis assay and molecular docking assay were used to determine the inhibitory effect and mechanism of demethylzeylasteral on the hydrolytic activity of the NDM-1 protein.Secondly,the synergistic bacteriostatic effect of demethylzeylasteral with the carbapenem antibiotic meropenem was confirmed by the checkerboard minimum inhibitory concentration assay,growth curve assay,and inhibition zone assay.The synergistic bactericidal effect of the combination was further determined by the time-killing assay,live/dead bacterial staining assay,and membrane integrity assay.Finally,the G.mellonella infection model demonstrated the protective effect of demethylzeylasteral and meropenem.The results indicated that demethylzeylasteral significantly inhibited the hydrolytic activity of NDM-1(IC_(50)=0.32 mg/L)and competitively affected the binding of NDM-1 to meropenem.In vitro tests showed that demethylzeylasteral had good a synergistic antibacterial effect with meropenem and could exert a synergistic bactericidal effect by enhancing the membrane damage of bacteria caused by meropenem.In vivo assays demonstrated that demethylzeylasteral increased the protective effect of meropenem from 67%to 80%.The results obtained in this study provide a therapeutic strategy and antibacterial synergist for treating NDM-1-positive bacterial infections.
作者
刘智营
郭岩
徐蕾
刘洪涛
邓旭明
邱家章
LIU Zhiying;GUO Yan;XU Lei;LIU Hongtao;DENG Xuming;QIU Jiazhang(College of Veterinary Medicine,Jilin University,Changchun 130062,China)
出处
《中国兽医学报》
CAS
CSCD
北大核心
2024年第8期1765-1772,共8页
Chinese Journal of Veterinary Science
基金
国家重点研发计划青年科学家基金资助项目(2021YFD1801000)。
关键词
去甲泽拉木醛
NDM-1
美罗培南
协同抗菌
demethylzeylasteral
NDM-1
meropenem
synergistic antibacterial activity
