Worldwide, Listeria monocytogenes is a common foodborne pathogen and serotyping is necessary for traceability and surveillance. Due to high accuracy and speed, PCR is commonly used for serotyping by targeting specific genes, such as lmo1118 and ORF2110 for 1/2c-3c and 4b-4d-4e, respectively. Single nucleotide polymorphisms (SNPs) are single base alterations at specific loci which are associated with various phenomena. In this study, a method was explored to mine specific SNPs from 253 L. monocytogenes genomes with known serotypes by writing Python programming language script. After blasting all the CDS, seventeen candidate genes with specific SNPs were obtained and these genes contained multiple types of SNPs, including lineages I, II, III, 1/2a-3a, 1/2b-3b-7, and 1/2c-3c specific SNPs. The sensitivity and specificity of these candidate SNP sites are higher than 85% in the genomes examined. Combining lineage I-specific, lineage II-specific, 1/2b-3b-7-specific, and 1/2c-3c-specific SNP sites together, using allele-specific multiplex PCR, we could serotype major L. monocytogenes serotypes. This method was used for 60 L. monocytogenes strains isolated from various food samples and the serotyping results were 100% identical to those of the currently accepted method with the reduced primers from ten to eight. Our results indicate that allele-specific multiplex PCR after mining specific SNPs from common genome database can be used for bacterial typing.

在世界范围内，单核细胞增生李斯特菌是一种常见的食源性病原体，为了进行追溯和监测，必须进行血清分型。由于准确性高和速度快，PCR通常通过靶向特定基因（例如分别针对1 / 2c-3c和4b-4d-4e的lmo1118和ORF2110）来进行血清分型。单核苷酸多态性（SNP）是特定基因座上的单碱基改变，与各种现象有关。在这项研究中，探索了一种从253种单核细胞增生李斯特菌中挖掘特定SNP的方法。通过编写Python编程语言脚本，获得具有已知血清型的基因组。爆破所有CDS后，获得了17个具有特定SNP的候选基因，这些基因包含多种SNP，包括I，II，III，1 / 2a-3a，1 / 2b-3b-7和1 / 2c- 3c特定SNP。这些候选SNP位点在检测的基因组中的敏感性和特异性都高于85％。通过使用等位基因特异性多重PCR将血统I特异性，血统II特异性，1 / 2b-3b-7特异性和1 / 2c-3c特异性SNP位点结合在一起，我们可以对主要的单核细胞增生李斯特菌血清型进行血清分型。该方法用于60种单核细胞增生李斯特菌从各种食物样品中分离得到的菌株，其血清分型结果与目前接受的方法的引物从10减少到8的100％相同。我们的结果表明，从公共基因组数据库中挖掘特定SNP后，等位基因特异性多重PCR可用于细菌分型。