Al-Adhami Batol H, Huby-Chilton Florence, Blais Burton W, Martinez-Perez Amalia, Chilton Neil B, Gajadhar Alvin A
Centre for Food-Borne and Animal Parasitology, Canadian Food Inspection Agency, Saskatoon, Saskatchewan, Canada.
J Food Prot. 2008 Oct;71(10):1960-6. doi: 10.4315/0362-028x-71.10.1960.
A molecular typing technique was developed for the differentiation of Salmonella isolates based on single-strand conformation polymorphism (SSCP) analysis of amplicons generated by PCR. Amplicons from parts of the fimA (both the 5' and 3' ends), mdh, invA, and atpD genes were generated separately from a panel of Salmonella strains representing Salmonella bongori, and four subspecies and 17 serovars of Salmonella enterica. These amplicons were subjected to SSCP analysis for differentiation of the salmonellae on the basis of different conformational forms arising due to nucleotide sequence variations in the target genes. Several distinct SSCP banding patterns (a maximum of 14 each for atpD and fimA 3' end) were observed with this panel of Salmonella strains for amplicons generated from each target gene. The best discrimination of Salmonella subspecies and serovar was achieved from the SSCP analysis of a combination of at least three gene targets: atpD, invA, and either mdh or fimA 3' end. This demonstrates the applicability of SSCP analysis as an important additional method to classical typing approaches for the differentiation of foodborne Salmonella isolates. SSCP is simple to perform and should be readily transferable to food microbiology laboratories with basic PCR capability.
基于聚合酶链反应（PCR）扩增产物的单链构象多态性（SSCP）分析，开发了一种用于区分沙门氏菌分离株的分子分型技术。从一组代表邦戈尔沙门氏菌、肠炎沙门氏菌的四个亚种和17个血清型的沙门氏菌菌株中分别扩增出fimA基因的部分片段（5'端和3'端）、mdh、invA和atpD基因。根据目标基因核苷酸序列变异产生的不同构象形式，对这些扩增产物进行SSCP分析以区分沙门氏菌。对于从每个目标基因产生的扩增产物，在这组沙门氏菌菌株中观察到了几种不同的SSCP条带模式（atpD和fimA 3'端各最多14种）。通过对至少三个基因靶点（atpD、invA以及mdh或fimA 3'端）的组合进行SSCP分析，能够最好地区分沙门氏菌亚种和血清型。这证明了SSCP分析作为传统分型方法的重要补充方法，可用于区分食源性病原体沙门氏菌分离株。SSCP操作简单，应可轻松转移至具备基本PCR能力的食品微生物实验室。
