动物源粪肠球菌的遗传关系分析

Abstract

目的：为了探讨不同动物来源中粪肠球菌(E.faecais)菌株之间的遗传关系。方法：利用PCR技术对59株不同来源粪肠球菌的7个管家基因gdh、gyd、pstS、gki、aroE、xpt、yiqL分别进行扩增测序，根据测序结果，利用多位点序列分型技术(Multilocus Sequence Typing, MLST)进行分析、比对。结果：59株不同来源粪肠球菌被分成了27个序列型(Sequence type, ST)，其中，主要流行序列型是ST-16 (占16.9%)，其次是ST-163 (占6.8%)、ST-238 (占6.8%)和ST-631 (占6.8%)，而与医院内感染密切相关的ST-16序列型，广泛分布在除熟食食品和羊粪外的其它5种来源中。另外，猪和蜂猴的粪便中分别含有7种序列型，且均有ST-16序列型。结论：多种动物来源中均含有感染人的粪肠球菌序列型，这也为粪肠球菌致病机理研究奠定了基础。 Objective: To explore the genetic relationships of E.faecais originating from different animal origions. Methods :The seven housekeeping genes including gdh, gyd, pstS, gki, aroE, xpt and yiqL of all 59 E.faecais originating from different animal origions were amplified by PCR method and sequenced, respectively. The sequences were analyzed by multilocus sequence typing technique (Multilocus Sequence Typing, MLST). Results: The 59 E.faecais were divided into 27 sequences type (Sequence type, ST), among them, the major epidemic sequence was ST-16 (16.9%), followed byST-163 (representing 6.8%), ST-238 (6.8%) and ST-631 (6.8%), and is closely related to nosocomial infection of ST-16 sequence type, the ST-16 Sequence type associated with clinical infection were widely distributed in slow loris, chicken-origin, lesion viscera, fresh pork and pig dung. Additionally, seven sequences type were widely distributed in the pig and slow loris stool. And, all of them have ST-16 sequence type. Conclusion: A variety of animal sources contain the dung enterococcus sequence of infected people, it also laid the basis for study of pathogenesis in E. faecalis.