天津地区鸡源沙门氏菌的基因分型研究

Study on the gene typing of Salmonella from chickens in Tianjin

目的研究并评估几种分子分型方法对亲缘关系相近鸡源沙门氏菌的分辨能力。方法针对2015—2016年从天津市大型市场和超市中分离的106株沙门氏菌及其全基因组测序结果,分析了沙门氏菌的血清型、序列类型(sequence types,STs),并通过脉冲场凝胶电泳(pulsed-field gel electrophoresis,PFGE)、核心基因组多位点序列分型(core genome multilocus sequence typing,cgMLST)以及一种基于59个基因的分型方法对沙门氏菌进行分子分型研究。结果106株沙门氏菌共分为8种血清型和8个ST型;PFGE分型方法将沙门氏菌分为7个集群;cgMLST将沙门氏菌分为8个集群;59个基因的分型方法将亲缘关系相近的分离株分为9个集群。结论肠炎沙门氏菌为这些沙门氏菌中的优势亚型;cgMLST具有最高的分辨率;基于59个基因的分型方法可以满足对亲缘关系相近沙门氏菌的分型研究。

Objective To investigate and evaluate the discrimination ability of several typing methods for Salmonella from chickens with similar genetic relationships.Methods Based on the whole genome sequencing results from 106 Salmonella strains isolated from large market and supermarket in Tianjin from 2015 to 2016,the serotype,sequence types(STs)were analyzed,and the molecular typing of Salmonella was studied by 3 typing methods:Pulsed-field gel electrophoresis(PFGE)method,core genome multilocus sequence typing(cgMLST)method and a typing method based on 59 functional genes.Results The 106 Salmonella strains were divided into 8serotypes and 8 ST types.These Salmonella were divided into 7 clusters by PFGE method and 8 clusters by cgMLST,and the strains with similar relationships were divided into 9 clusters by 59-gene based typing method.Conclusion Salmonella enteritidis is the advantageous subtype of these Salmonella.The cgMLST shows the highest resolution.The typing method based on 59 genes can be used to study the typing research of Salmonella with close relationship.