采用高级微生物基因分型系统对食品中单核细胞增生李斯特菌进行同源性分析

采用高级微生物基因分型系统(DiversiLab系统)对食品中单核细胞增生李斯特菌进行基因型分析,将分型结果与血清型和菌株的耐药性进行比对研究。方法 DiversiLab系统是基于rep-PCR原理对微生物进行分型,将分型结果与菌株的血清型进行比较研究,同时对菌株的耐药性与rep-PCR型别进行研究。结果 采用DiversiLab系统将46株单核细胞增生李斯特菌分为9个型别A～I。血清型为1/2a的分离株以A型为主,所测试的6株血清型为4b的分离株均为H型；14株呋喃妥因耐受菌株9株为A型、1株为B型、3株为C型、1株为F型,除2株血清型为3a外,其余均为1/2a。结论 DiversiLab系统分析结果,揭示了46株从食品中分离的单增细胞增生李斯特菌间的亲缘关系,rep-PCR分型结果与H抗原结合位点存在一定联系,呋喃妥因耐受菌株的DNA指纹图谱相似度高,与耐药基因有关。

Typing Listeria monocytogenes isolated from food by DiversiLab system

L.monocytogenes isolates were typed by DiversiLab system. The result was compared with the results of serotype and the antibiotic resistance.MethodsThe DiversiLab system was based on the principle of rep-PCR. ResultsThe 46 isolates were classified as nine types, type A to I. The 1/2a serotype isolates mainly belonged to A type. Six 4b serotype isolates belonged to H type. Among 14 nitrofurantoin resistance isolates, nine of them were A type, one isolate was B type, three isolates were C type, and one isolate was F type. Most of the nitrofurantoin resistance isolates were 1/2a serotype, except two of them were 3a serotype.ConclusionDiversiLab system typing results revealed the genetic characters and relationship of 46 foodborne L.monocytogenes. The typing results related to the H sites of serotype. The similarity of 14 nitrofurantoin resistance isolates was high, and related to anti-nitrofurantoin resistance genes.