弯曲菌中氟苯尼考耐药基因fexA功能鉴定及其携带质粒分析  

Functional Identification of the Florfenicol-resistant Gene fexA in Campylobacter and Analysis of Plasmid Carrying This Gene

作　　者：陈宇[1] 焦典 赵文博 张程 姚红 CHEN Yu;JIAO Dian;ZHAO Wen-bo;ZHANG Cheng;YAO Hong(College of Veterinary Medicine,Henan Agricultural University,Zhengzhou 450046,China)

机构地区：[1]河南农业大学动物医学院,河南郑州450046

出　　处：《中国兽医杂志》2023年第10期40-45,共6页Chinese Journal of Veterinary Medicine

基　　金：国家自然科学基金项目(31802239);河南省优秀青年科学基金项目(232300421037)。

摘　　要：为确证氟苯尼考耐药基因fexA在弯曲菌中的功能并分析fexA基因遗传环境,本试验采用药物敏感性试验、聚合酶链式反应(PCR)、fexA单基因克隆、电转化、全基因组测序和分析方法对fexA基因功能进行鉴定,并基于全基因组序列对fexA基因环境进行分析。结果显示:氟苯尼考对构建的单基因克隆11168-fexA菌株最小抑菌浓度(MIC)值为32μg/mL,比受体菌株NCTC 11168对氟苯尼考的MIC值提高了32倍;fexA基因定位于长度为13793 bp的新型质粒(pC19-fexA),该质粒不能通过电转化转移至受体菌。综上所述,fexA基因可介导弯曲菌对氟苯尼考的高水平耐药表型;携带fexA基因的质粒虽然不能通过电转化发生水平传播,但其作为fexA基因的新型载体应得到关注。In order to confirm the functionality of the florfenicol-resistant gene fexA in Campylobacter and to analyze the genetic environment of the fexA gene,this study employed antimicrobial susceptibility testing,polymerase chain reaction(PCR),fexA single gene cloning,electroporation,whole genome sequencing,and analytical methods to identify the function of the fexA gene.Furthermore,an analysis was performed on the genetic environment of the fexA gene based on whole genome sequences.The results revealed that the minimum inhibitory concentration(MIC)of florfenicol for the constructed single gene clone,11168-fexA,was 32μg/mL,which was 32 fold higher than the MIC for the recipient strain NCTC 11168.The fexA gene was located on a novel plasmid of 13793 bp in length(pC19-fexA),which could not be transferred to the recipient strain through electroporation.In conclusion,the fexA gene can mediate high-level florfenicol-resistant phenotype in Campylobacter.Although plasmids carrying the fexA gene may not be horizontally transferred through electroporation,their role as a novel carrier for the fexA gene should be noted.

关 键 词：弯曲菌 氟苯尼考 耐药性 fexA 

分 类 号：S855.1[农业科学—临床兽医学]