碳青霉烯耐药质粒接合效率的评价方法比较  

Comparison of Evaluation Methods for Conjugation Efficiency of Carbapenem-Resistant Plasmids

作　　者：孙育坤 张铭洋 公啸 邹明[1] 刘宝涛[1] SUN Yu-kun;ZHANG Ming-yang;GONG Xiao;ZOU Ming;LIU Bao-tao(College of Veterinary Medicine,Qingdao Agricultural University,Qingdao 266109,China;Pingyi County Animal Husbandry Development Promotion Center,Linyi 273300,China)

机构地区：[1]青岛农业大学动物医学院,山东青岛266109 [2]临沂市平邑县畜牧发展促进中心,山东临沂273300

出　　处：《中国兽医杂志》2023年第9期88-92,共5页Chinese Journal of Veterinary Medicine

基　　金：青岛市科技惠民示范引导专项(21-1-4-ny-10-nsh,21-1-4-ny-11-nsh);山东省牛产业技术体系项目(SDAIT-09-11);山东省自然科学基金(ZR2022MC001);山东省重大科技创新工程项目(2019 JZZY010719)。

摘　　要：为探讨碳青霉烯类药物对接合效率的影响,并分析接合试验过程中是否由于接合子的生长导致接合效率被高估,本试验以3株分别携带不同碳青霉烯耐药质粒的菌株ML83、WF1321和VH12为供体菌,大肠杆菌C600为受体菌,采用不同亚抑菌浓度的美罗培南分别处理供体菌和受体菌,分别采用传统方法(接合效率=接合子数÷受体菌数)和真实接合效率方法[接合效率=接合子数÷(供体菌数×受体菌数×接合时间)]对碳青霉烯耐药质粒的接合效率进行评价。结果显示,与不加药物的对照组相比,不同亚抑菌浓度的美罗培南对碳青霉烯耐药质粒的接合转移均有促进作用(P<0.05),且促进作用随着美罗培南浓度的升高而增大;与真实接合效率方法相比,传统方法获得的接合效率更高,但真实接合效率方法得到的接合效率组间差异性更显著。结果表明,细菌真实的接合效率被高估,真实接合作用主要发生在前期指数对数期,后期极有可能是由于接合完成后接合子的生长导致总接合效率的升高。To investigate the impact of carbapenem antibiotics on conjugation efficiency and analyze whether overestimation of conjugation efficiency occurs due to the growth of transconjugants during the conjugation process,this study used three strains,ML83,WF1321,and VH12,each carrying different carbapenem-resistant plasmids,as donor strains,and Escherichia coli C600 as the recipient strain.Different sub-inhibitory concentrations of meropenem were applied to treat both donor and recipient strains.Conjugation efficiency of carbapenem-resistant plasmids was evaluated using both traditional method(conjugation efficiency=number of transconjugants÷number of recipient cells)and real conjugation efficiency method[conjugation efficiency=number of transconjugants÷(number of donor cells×number of recipient cells×conjugation time)].The results demonstrated that different sub-inhibitory concentrations of meropenem promoted the transfer of carbapenem-resistant plasmids compared with the control group without drug treatment(P<0.05).The promotion effect increased with higher meropenem concentrations.Compared with the real conjugation efficiency method,the traditional method yielded higher conjugation efficiency,but the differences in conjugation efficiency between groups were more significant using the real conjugation efficiency method.These findings indicate that the actual conjugation efficiency of bacteria is overestimated,and the real conjugation mainly occurs during the early exponential phase.The late phase is likely attributed to the growth of conjugants after conjugation completion,leading to an increase in total conjugation efficiency.

关 键 词：大肠杆菌 碳青霉烯 接合效率 评价方法 

分 类 号：S859[农业科学—临床兽医学]