肉与肉制品空肠弯曲菌耐药性和多位点序列分型

Antimicrobial resistance in and multilocus sequence typing of Campylobacter jejuni in meat and meat products

目的了解辽宁省肉与肉制品中分离的空肠弯曲菌的耐药性和多位点序列分型(MLST),为防治食源性空肠弯曲菌感染提供依据。方法于2020年对9株分离自肉与肉制品检测样品的空肠弯曲菌进行全基因组测序,采用琼脂稀释法检测最低抑菌浓度,分析菌株耐药性。采用微生物耐药机制溯源参比数据库及分析系统鉴定MLST型别。结果检出耐药株6株,多重耐药株4株。对四环素、萘啶酸、环丙沙星、氟苯尼考、庆大霉素和链霉素耐药分别为6、5、4、2、1和1株;对阿奇霉素、氯霉素和克林霉素敏感。9株空肠弯曲菌检出6种ST型别,以ST45和ST2274为主,ST未分型1株。ST45型的KW028和KW029亲缘关系较近,同源性较高;ST2274型的KW040和KW042亲缘关系较近,同源性较高;ST6701型的KW007与ST2274型的KW040、KW042遗传亲缘关系较近,仅相差1个pgm管家基因。结论9株分离自肉与肉制品检测样品的空肠弯曲菌对四环素、萘啶酸和环丙沙星耐药率较高,以ST45和ST2274为主。

Objective To investigate the antimicrobial resistance in and multilocus sequence typing(MLST)of Campylo⁃bacter jejuni in meat and meat products in Liaoning Province,so as to provide insights into the management of C.jeju⁃ni infection.Methods Nine C.jejuni isolates from meat and meat products in 2020 were subjected to whole genome sequencing,and the minimum inhibitory concentration was measured with the agar dilution method.MLST of C.jejuni isolates was performed with the microbial resistance mechanism traceability reference database and analysis system.Re⁃sults Six drug-resistant C.jejuni isolates were detected,and there were four multidrug-resistant isolates.There were six C.jejuni isolates resistant to tetracycline,five isolates resistant to nalidixic acid,four isolates resistant to ciprofloxa⁃cin,two isolates resistant to florfenicol,one isolate resistant to gentamicin and one isolate resistant to streptomycin.Nine C.jejuni isolates showed sensitive to azithromycin,chloramphenicol and clindamycin.MLST identified six ST types in nine C.jejuni isolates,with ST45 and ST2274 as the predominant type,and detected one isolate with unclassified ST type.Phylogenetic analysis showed that KW028 and KW029 of ST45 type were closely related and had high homolo⁃gy,and KW040 and KW042 of ST2274 type were closely related with high homology,while KW007 of ST6701 type was closely related to KW040 and KW042 of ST2274 type,with only one pgm housekeeper gene in difference.Conclu⁃sions High resistance to tetracycline,nalidixic acid and ciprofloxacin was detected in nine C.jejuni isolates from meat and meat products,and ST45 and ST2274 were predominant ST types of C.jejuni.