摘要
为了探索CpxAR和AcrAB-tolC的协同作用对鼠伤寒沙门菌多重耐药性的调控机制,利用噬菌体转导技术,以前期构建的鼠伤寒沙门菌(JS)的tolC缺失株JSΔtolC::kan为供体菌,以cpxR缺失株JSΔcpxR为受体菌,在P22噬菌体的作用下成功构建了JS的双基因缺失株JSΔcpxRΔtolC::kan;再利用pCP20质粒消除卡那抗性基因kan,获得了JSΔcpxRΔtolC,并构建了cpxR回补株JSΔcpxRΔtolC/p cpxR。采用微量肉汤稀释法测定了12种常用抗菌药物的最小抑菌浓度(MIC)。结果显示:tolC缺失株对环丙沙星、头孢噻肟、头孢喹肟、多西环素、痢菌净、喹乙醇、头孢噻呋、氟苯尼考、土霉素、恩诺沙星、阿米卡星的MIC值分别降低至JS的1/8、1/2、1/4、1/8、1/8、1/2、1/16、1/4、1/4、1/8、1/2;cpxR和tolC双基因缺失株对头孢噻肟、头孢喹肟、多西环素、痢菌净、喹乙醇、恩诺沙星的MIC均又进一步降低至tolC缺失株的1/2;而将cpxR基因回补到双基因缺失株JSΔcpxRΔtolC中后,对环丙沙星、头孢噻肟、头孢噻呋的MIC值均升高了2倍,对恩诺沙星的MIC升高至4倍,对头孢喹肟的MIC升高了8倍。说明cpxR缺失与tolC缺失的协同作用能增强鼠伤寒沙门菌对头孢噻肟、头孢喹肟、多西环素、痢菌净、喹乙醇、恩诺沙星的敏感性。
In order to explore the regulation mechanism of CpxAR and AcrAB-tolC on the multidrug resistance of Salmonella typhimurium,by phage transduction technology,the double gene deletion strain JSΔcpxRΔtolC::kan was constructed by phage P22-mediated transduction with the JSΔtolC::kan as the donor and the JSΔcpxR as the recipient in the previous study,and then the pCP20 plasmid was used to eliminate kan,and the JSΔcpxRΔtolC was obtained.Meanwhile,the cpxR complemental strain JSΔcpxRΔtolC/p cpxR was constructed.At last,the minimum inhibitory concentration(MIC)of 12 antibacterial drugs was determined by microdilution method.The results showed that the tolC gene-deficient strain showed 1/8,1/2,1/4,1/8,1/8,1/2,1/16,1/4,1/4,1/8 and 1/2 fold decrease in the MICs of ciprofloxacin,cefotaxime,cefquinoxime,doxycycline,mequindox,olaquindox,ceftiofur,florfenicol,oxytetracycline,ceftriaxone,enrofloxacin and amikacin.The cpxR and tolC double gene deletion strains showed 1/2 fold decrease in the MICs of cefotaxime,cefquinoxime,ciprofloxacin,cefotaxime,olaquindox and enrofloxacin compared with the JSΔcpxRΔtolC::kan.While the complemental strain JSΔcpxRΔtolC/p cpxR showed 2,2,2,4,8 fold increase in the MICs of ciprofloxacin,cefotaxime sodium,ceftiofur,cefquinome and enrofloxacin compared with the JSΔcpxRΔtolC.In conclusion,the synergistic effect of cpxR deletion and tolC deletion can increase the sensitivity of Salmonella typhimurium to cefotaxime,cefquinoxime,doxycycline,mequindox,olaquindox and enrofloxacin.
作者
张梦珂
崔小蝶
吴华
罗行炜
刘建华
翟亚军
贺丹丹
潘玉善
苑丽
胡功政
ZHANG Meng-ke;CUI Xiao-die;WU Hua;LUO Xing-wei;LIU Jian-hua;ZHAI Ya-jun;HE Dan-dan;PAN Yu-shan;YUAN Li;HU Gong-zheng(College of Veterinary Medicine,Henan Agricultural University,Zhengzhou 450002,China)
出处
《江西农业学报》
CAS
2021年第7期93-98,103,共7页
Acta Agriculturae Jiangxi
基金
国家自然科学基金项目(32072913)。
作者简介
张梦珂(1993-),女,河南汝州人,博士研究生,主要从事抗感染药物药理及细菌耐药性研究;通信作者:胡功政。