基于全基因组测序的蜡样芽孢杆菌食品分离株分子特征及耐药性研究  

Molecular characteristics and antibiotic resistance of Bacillus cereus from foods using whole genome sequencing

作　　者：张红芝[1] 刘雪薇 顾其芳[1] 常兆玉 朱彦祺 张曦[1] ZHANG Hongzhi;LIU Xuewei;GU Qifang;CHANG Zhaoyu;ZHU Yanqi;ZHANG Xi(Shanghai Municipal Center for Disease Control and Prevention,Shanghai 200336,China)

机构地区：[1]上海市疾病预防控制中心,上海200336

出　　处：《中国食品卫生杂志》2021年第5期529-535,共7页Chinese Journal of Food Hygiene

基　　金：上海市公共卫生体系建设三年行动计划(GWV-2)。

摘　　要：目的研究上海市食品中分离的蜡样芽孢杆菌(Bacillus cereus)的基因组特征及其耐药性。方法本研究对上海市食品中分离的蜡样芽孢杆菌进行鉴定、药物敏感性实验和全基因组测序,利用BioNumerics软件对测序数据进行拼接组装,利用拼接数据进行多位点序列分型(MLST)、毒力基因和耐药基因分析,并与PubMLST数据库中的ST型进行比较;对耐药基因和耐药表型进行比较分析。结果本研究中37株蜡样芽孢杆菌均可分型,其中7株为ST新型。37株蜡样芽孢杆菌分为34个ST型,其中3株菌为ST26型,其余ST型各占1株,呈高度多样性。37株蜡样芽孢杆菌均携带nheA、nheB、nheC基因,hblACD基因簇的携带率为37.8%,而完整ces呕吐基因簇的携带率只有16.2%,其中2株为分离自即食食品的ST26型。药敏实验显示37株蜡样芽孢杆菌对氨苄西林、青霉素和苯唑西林耐药性较高,与其携带耐药基因种类并不完全一致。结论上海市食品中分离的蜡样芽孢杆菌菌株分子分型呈现高度多样性,应加强食品中蜡样芽孢杆菌分子生物学监测,为预防控制由其引起的食源性疾病提供科学依据。Objective To study the molecular characteristics and antibiotic resistance of Bacillus cereus(B.cereus)from foods in Shanghai.Methods The B.cereus isolates were characterized using antibiotic susceptibility tests and whole genome sequencing(WGS).BioNumerics software was used to analyze and assemble WGS data.Then,multilocus sequence typing(MLST),virulence genes profiles and antibiotic resistant genes were analyzed using assembled genome sequences.The antimicrobial susceptibility was investigated.Furthermore,STs of B.cereus in this study were compared with those from PubMLST database.Results In this study,all 37 isolates were confirmed as B.cereus isolates.The 37 B.cereus were typed into 34 STs with 7 new STs.The result of STs showed high diversity.All 37 B.cereus isolates had nheA,nheB and nheC genes.The positive rate of hblACD genes was 37.8%.However,only 16.2%of B.cereus had ces genes.Furthermore,two ST26 B.cereus isolates with ces genes from ready-to-eat food were identified.The antibiotic resistance rate to Ampicillin,Penicillin and Oxacillin was high,which was not consistent with antibiotic resistant genes.Conclusion The STs of 37 B.cereus from food in Shanghai showed high genetic diversity,which suggested the molecular surveillance should be enhanced.Fundamental data can be obtained using whole genome sequencing for tracing B.cereus isolates and analyzing pathogenicity.

关 键 词：蜡样芽孢杆菌 全基因组测序 多位点序列分型 毒力基因谱 耐药性 

分 类 号：R155[医药卫生—营养与食品卫生学]