摘要
本试验鉴定禽源耐药大肠杆菌1株,命名为Coli0,其小檗碱亚抑菌质量浓度(1/2 MIC)为250 mg/L。药敏试验显示Coli0对左氧氟沙星、头孢菌素、庆大霉素和氨苄等9种抗生素耐药。经小檗碱处理后多耐药大肠杆菌对左氧氟沙星耐药性部分消除,得到耐药消除菌5株,分别命名为Coli1、Coli2、Coli3、Coli4和Coli5。对Coli0菌株进行全基因组测序,显示其基因组由1个序列长度为4858944 bp的核DNA和2个质粒DNA组成,注释得到的基因总数4883个,耐药基因67个。对Coli0和Coli1进行耐药基因荧光定量PCR,结果显示小檗碱处理后共有18个耐药基因发生显著变化,其中acrR、mexE、sul2、mdtH、mdtL、cpxR、phoQ和pmrC显著下调,mdtE、gyrA、gyrB、macA和macB显著上调,bacA、acrE和emrK消失,mdtA和baeR新产生。小檗碱通过阻碍大肠杆菌多药耐药外排泵表达,影响细胞壁合成,导致耐药质粒丢失和上调抗生素靶蛋白表达等多方面影响细菌抗药性。而macAB耐药外排泵活性增强可能是细菌抵抗小檗碱的反应,这预示着尽管Coli0和Coli1小檗碱的MIC并未改变,大肠杆菌可能会对小檗碱也有耐药现象。
Coli0 was identified as E.coli that berberine sub-bacteriostasis concentrationts(1/2 MIC)was 250 mg/L and resistance to 9 antibiotic.After treatment with berberine,five bacteria were obtained,named Coli1,Coli2,Coli3,Coli4 and Coli5.The total genetic information of Coli0 was composed of 4808,944 bp nuclear DNA and 2 plasmid DNAs.A total of 4883 genes were found which included 67 resistant genes.The results of quantitative PCR showed that there were 18 drug resistance genes changes in E.coli after treatment with berberine.Among them,acrR,mexE,sul2,mdtH,mdtL,cpxR,phoQ,pmrC were significantly downregulated;mdtE,gyrA,gyrB,macA,macB were significantly upregulated;bacA,acrE,emrK disappeared;mdtA,baeR appeared.Berberine can change the antibiotic resistance of E.coli by blocking the multidrug resistance efflux pump,inhibiting cell wall synthesis,causing drug-resistant plasmid loss and up-regulate the expression of antibiotic target protein.However,the increase of macAB might indicates that E.coli may be resistant to berberine.
作者
张石磊
翟向和
王春光
贾泽
张铁
ZHANG Shi-lei;ZHAI Xiang-he;WANG Chun-guang;JIA Ze;ZHANG Tie(College of Animal Science and Technology,Hebei Agricultural University,Baoding,Hebei 071001,China;College of Traditinonal Chinese Veterinary Medcine,College of Veterinary Medicine,Hebei Agricultural University,Baoding,Hebei 071001,China)
出处
《中国兽医学报》
CAS
CSCD
北大核心
2020年第9期1737-1745,共9页
Chinese Journal of Veterinary Science
基金
国家自然科学基金资助项目(31572560)
河北省重点研发计划资助项目(16222701D)。
关键词
小檗碱
大肠杆菌
多药耐药
全基因组测序
荧光定量PCR
berberine
Escherichia coli
multidrug resistance
whole genome sequencing
fluorescence quantitative PCR
