新疆食源性单增李斯特菌MLST分型及耐药性分析

Multilocus sequence typing and antibiotic resistance of food-borne Listeria monocytogenes in Xinjiang

目的研究新疆食源性单增李斯特菌分型和耐药情况。方法将62株食源性和1株羔羊脑炎分离株进行多位点序列分型(multilocus sequence typing,MLST)及耐药性实验。结果 63株单增李斯特菌分为20个ST型, 16个克隆群(clonal complex groups, CC),其中68.25%(43/63)属于谱系Ⅱ,其余属于谱系Ⅰ。优势ST型是ST8、ST9、ST121、ST87和ST378,优势CC群是CC8、CC9、CC1和CC121。对苄青霉素(penicillin, P)、氨苄西林(ampicillin, AM)、苯唑西林(oxacillin, OX1) 3种抗生素耐药率达100%;对庆大霉素(gentamicin, GM)、莫西沙星(moxifloxacin,MXF)、红霉素(erythromycin,E)、奎奴普丁/达福普丁(quinupristin,QDA)、利奈唑胺(linezolid, LNZ)、万古霉素(vancomycin, VA)、替加环素(tigecycline, TGC)、利福平(rifampin, RA)和诱导性克林霉素耐性(induced clindamycin resistance, ICR) 9种抗生素敏感率达100%;对呋喃妥因(furadantin, FT)耐药率61.90%(39/63),其中ST7、ST8、ST101、ST155和ST515对此次的3-4类药物表现出多重耐药性。结论新疆单增李斯特菌分子型别呈多样性,耐药谱变宽,存在较大的食品安全风险。

Objective To study the typing and antibiotic resistance of food-borne monotonic Listeria monocytogenes in Xinjiang. Methods A total of 63 Listeria monocytogenes strain were tested for multilocus sequence typing(MLST) and antibiotic resistance. Results Sixty-three strains were divided into 20 ST types, ST8, ST9, ST121, ST87 and ST378 were being the dominant types. And 16 clonal complex groups(CC), the dominant CC groups were CC8, CC9, CC1 and CC121. The 68.25%(43/63) belonged to lineages Ⅱ, and the rest belonged to lineages Ⅰ. The antibiotic resistance rate of Listeria monocytogenes to penicillin, ampicillin and oxacillin was 100%, to gentamicin, moxifloxacin, erythromycin, quinupristin, linezolid, vancomycin, tigecycline, rifampin and induced clindamycin resistance was 100%, to furadantin was 61.90%(39/63). ST7, ST8, ST101, ST155 and ST515 showed multiple resistance to the 3-4 drugs. Conclusion The molecular type of Listeria monocytogenes is polymorphicin Xinjiang, the antibiotic resistance spectrum is widening, and there is a big food safety risk.