天津地区鸡源沙门氏菌的基因分型研究

目的 研究并评估几种分子分型方法对亲缘关系相近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、STs,并通过PFGE、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(肠炎沙门氏菌(n=94)、印第安纳沙门氏菌(n=4)、肯塔基沙门氏菌(n=2)、哈达尔沙门氏菌(n=2)、汤普森沙门氏菌(n=1)、鼠伤寒沙门氏菌(n=1)、田纳西沙门氏菌(n=1)和阿哥纳沙门氏菌(n=1))和8个ST型；PFGE分型方法将沙门氏菌分为7个集群,cgMLST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 血清型分析表明肠炎沙门氏菌为这些沙门氏菌中的优势亚型,并与ST型结果一致；PFGE显示7个集群中包含一个优势集群,多为肠炎亚型；cgMLST具有最高的分辨率,将106株沙门氏菌分为8个集群；建立的基于59个基因的分子分型方法将沙门氏菌分为9个集群,分型结果表明此方法可以满足对亲缘关系相近沙门氏菌的分型研究。

Study on the gene typing of Salmonella from chickens in Tianjin

Objective Investigated and evaluated the resolution of several typing methods for Salmonella with similar genetic relationships. Methods For 106 Salmonella strains isolated from large market and supermarket in Tianjin for 2015-2016 years and the whole genome sequencing results, we analyzed the serotype, STs and the resolution of three typing methods: PFGE method, cgMLST method and a typing method based on 59 functional genes. Results The 106 Salmonella strains were divided into 8 serotypes (S. Enteritidis (n=94), S. Indiana (n=4), S. Kentucky (n=2), S. Hadar (n=2), S. Thompson (n=1), S. Typhimurium (n=1), S. Tennessee (n=1) and S. Agona (n=1)) and 8 ST serotypes. These Salmonella were divided them into 7 clusters by PFGE method and 8 clusters by cgMLST, and the 91 isolates were divided into 9 clusters by 59-gene based typing method. Conclusion Serotype analysis showed that S. Enteritidis was the dominant subtype, which was consistent with the results of STs analysis. The results of PFGE showed that one of the seven clusters contained a dominant cluster, most of which were S. Enteritidis. The cgMLST had the highest resolution compared to other methods. The established molecular typing method based on 59 genes divides Salmonella into 9 clusters, and the typing results show that this method can satisfy the typing research of Salmonella with close relationship.