摘要
目的比较多位点序列分型技术和脉冲场凝胶电泳(PFGE)技术在肠炎沙门菌菌株间分型的分辨率。方法分别建立肠炎沙门菌的6个管家基因thrA、putE、sucA、aroC、hemD、dnaN和一个特异性的DNA标记SdfⅠ的多位点序列分型技术,及以寡切点的XbaⅠ、SpeⅠ作为限制性内切酶的PFGE方法,并应用上述方法对食品中的分离株进行分型,比较两种方法的分辨率。结果PFGE可以将50株肠炎沙门菌分为11个型,并且通过双酶系统的双重PFGE分型,还可以将PFGE型别再精细划分为亚型;MLST则揭示了在同一血清型内部,各菌株之间的管家基因碱基序列高度保守,而在沙门菌不同血清型的核苷酸序列之间,则分别存在不同数量的碱基差异。即MLST方法只能用于血清型之间,不能在血清型内部进行分型研究。结论与MLST比较,PFGE方法在肠炎沙门菌的分型方面显示了比较高的分辨率。
Objective To compare the discriminatory ability between multilocus sequence typing system （MLST） and pulsed-field gel electrophoresis （PFGE）. Methods Salmonella enteritidis strains, isolated from food in China were identified by MLST, under PCR products of thrA, purE, sueA, aroC, heroD, dnaN and Sdf Ⅰ. The same set of strains was typed by PFGE using Xba Ⅰ , Spe Ⅰ as the restriction enzyme in order to compare the discriminatory power of the methods. Results Data from MLST revealed the lack of diversity among the strains of the same serotype and the number of variable nucleotide sites per locus ranged from 1 to 23 between Salmonella typhi LT2 and other serotypes of Salmonella. However, 50 Salmonella enteritldis strains were identified as 11 patterns and more subpatterns by PFGE. Conclusion In strain typing, PFGE was the highly discriminatory method comparing to the MLST system.
出处
《中华流行病学杂志》
CAS
CSCD
北大核心
2006年第12期1065-1068,共4页
Chinese Journal of Epidemiology
基金
国家"十五"重大科技专项食品安全关键技术研究课题资助(2001BA804A3205)
关键词
肠炎沙门菌
多位点序列分型
脉冲场凝胶电泳
分辨率
Salmonella enteritidis
Multilocus sequence typing
Pulsed-field gel electrophoresis
Discriminatory ability
