进出口食品中不同血清型沙门氏菌PFGE和 MLST分型比较研究

目的：通过PFGE和MLST两种方法对进出口食品中不同血清型沙门氏菌的分辨力和应用价值进行了比较研究。方法：采用PFGE和MLST两种方法对进出口食品中分离得到的鼠伤寒及肠炎两种血清型共30株沙门氏菌进行分型研究。结果：两种血清型共30株沙门氏菌经PFGE分型可得到23种型别,DI值为0.9563；鼠伤寒和肠炎两种血清型菌分别经PFGE分型,DI值分别为1.000和0.9048。MLST对30株沙门氏菌分型得到4种ST型,DI值为0.5793；鼠伤寒和肠炎两种血清型菌分别经MLST分型,DI值分别为0.2571和0.1333。结论：在分辨力方面,PFGE更适合于同一沙门氏菌血清型的分型,MLST适合于不同沙门氏菌血清型间的分型。MLST在替代、补充血清型分型方面有潜在的优势,PFGE在溯源研究方面似乎更胜一筹。

Comparison of pulsed-field gel electrophoresis and multilocus sequence typing of Salmonella in import and export foods

Objective: To compare discriminatory ability and application value of PFGE and MLST in different Salmonella serotype of import-exported foods. Methods: All 30 strains of both Salmonella typhimurium and Salmonella enteritidis isolates which were separated from import and export foods were typed by PFGE and MLST. Results: All 30 strains Salmonella were divided into 23 PFGE types with Discriminatory index 0.9563 while they were divided into 4 ST types by MLST with Discriminatory index 0.5793. The Discriminatory index of Salmonella typhimurium and Salmonella enteritidis isolates typed by PFGE were 1.000 and 0.9048 with the contrast of 0.2571 and 0.1333 by MLST. Conclusions: In terms of discrimination, PFGE is more suitable for the same Salmonella serotype classification while MLST is suitable for different salmonella serotype. There are potential advantages for MLST in alternative and complementary serotype. But for PFGE, it is better in traceability research.