1株mphA和mcr-1阳性鼠伤寒沙门菌的鉴定及耐药特征分析  

Identification and antimicrobial resistance analysis of a strain of Salmonella typhimurium positive for mphA and mcr-1

作　　者：韩艺然 李欣平 朱坤鹏 彭玉倩 杨海燕[1] 邱少富 向莹 Han Yiran;Li Xinping;Zhu Kunpeng;Peng Yuqian;Yang Haiyan;Qiu Shaofu;Xiang Ying(College of Public Health,Zhengzhou University,Zhengzhou 450001;The Centre of Disease Control and Prevention of Chinese People's Liberation Army,Beijing 100071)

机构地区：[1]郑州大学公共卫生学院,郑州450001 [2]解放军疾病预防控制中心,北京100071

出　　处：《中国抗生素杂志》2023年第12期1409-1416,共8页Chinese Journal of Antibiotics

基　　金：国家自然科学基金(No.82202538,No.82173580)。

摘　　要：目的1株mphA和mcr-1阳性鼠伤寒沙门菌的鉴定及耐药特征分析;方法分离自4岁腹泻患者粪便样本中的1株鼠伤寒沙门菌,使用沙门菌血清凝集法进行菌株鉴定,质谱法复核鉴定结果;使用微量肉汤稀释法进行药敏试验;通过全基因组测序及耐药基因注释鉴定菌株所携带的耐药基因;通过质粒测序及生信分析进行质粒类型鉴定、质粒耐药基因、插入子等注释及质粒结构分析;通过质粒接合转移试验评估质粒的水平转移能力。结果药敏试验结果显示分离株对包括阿奇霉素、多黏菌素、头孢曲松和环丙沙星等临床常用抗生素药物耐药。耐药基因鉴定结果显示:该分离株携带包括大环内酯类抗性基因mphA,多黏菌素抗性基因mcr-1在内的12类45个耐药基因及1个氟喹诺酮类耐药点突变gyr A S83F。质粒测序分析结果显示:该菌株携带一个260,008bp大小的Inc HI2型质粒,该质粒携带包括mphA基因和mcr-1基因在内的19个耐药基因,15种插入子,4种转座子。质粒接合转移实验结果显示该质粒可以在肠杆菌目细菌之间水平转移。结论研究结果为临床治疗鼠伤寒沙门菌感染中合理使用抗生素以及有效预防、控制耐阿奇霉素、多黏菌素鼠伤寒沙门菌的传播提供了科学依据。Objective To identify a mphA and mcr-1-positive multidrug-resistant Salmonella typhimurium isolate and analyze its antimicrobial resistance.Methods The strain isolated from a fecal sample of a four years old kid and collected.The Salmonella strains were identified by serum agglutination method,the results were verified by mass spectrometry.The antimicrobial sensitivity test was conducted by microbroth dilution method.The antimicrobial resistance(AMR)genes were identified by whole genome sequencing and AMR genes annotation.Plasmid sequencing and bioinformatics analysis were used to identify plasmid types,annotate plasmid AMR genes and insertion sequences,analyze plasmid structure.The horizontal transfer ability of the plasmid was estimated by plasmid conjugative transfer assay.Results The results of antimicrobial sensitivity test showed that the isolates were resistant to commonly used antibiotics including azithromycin,colistin,ceftriaxone and ciprofloxacin.Identification of AMR genes showed that the isolated strain carried 45 AMR genes in 12 classes,including macrolide resistance gene mphA,colistin resistance gene mcr-1 and a point mutation in gyrA gene.Plasmid sequencing analysis showed that the strain carried a 260,008 bp size of IncHI2 plasmid,which carried 19 AMR genes,15 classes of insertion sequences and 4 classes of transposons.The results of plasmid conjugative transfer assay showed that the plasmid could be transferred horizontally between intestinal strains.Conclusion This study provides a scientific basis for guiding the rational application of antibiotics and curbing the continuous spread of bacterial resistance.

关 键 词：鼠伤寒沙门菌 耐药性 mphA mcr-1 质粒 

分 类 号：R278[医药卫生—中医学] R378