PDF(Pubmed)
Abstract：
Listeria monocytogenes is a human pathogen that has the ability to cause listeriosis, a disease with possible fatal outcomes. The typical route of infection is ingestion of the bacteria with contaminated food. In this study, 13 virulence-associated genes were examined with PCR in the genomes of 153 L. monocytogenes isolates collected from meat products and processing environments in Poland. All isolates possessed genes from LIPI-1-hly, actA, plcA, plcB and mpl-as well as four internalins: inlA, inlB, inlC, inlJ. Invasion-associated protein iap, as well as genes prfA and sigB, encoding regulatory proteins, were also detected in all isolates. Gene flaA, encoding flagellin, was detected in 113 (74%) isolates. This was the only gene that was not detected in all isolates, as its presence is serotype-dependent. Gene actA showed polymorphism with longer and shorter variants in PCR amplicons. Two isolates were characterized by truncated inlB genes, lacking 141 bp in their sequence, which was confirmed by gene sequencing. All isolates were positive in hemolysis assays, proving the synthesis of functional PrfA and Hly proteins. Four genotypes of L. monocytogenes based on actA polymorphism and two genotypes based on inlB polymorphism were distinguished within the isolates\' collection.
摘要：
单核细胞增生李斯特菌是一种人类病原体，具有引起李斯特菌病的能力，一种可能致命的疾病。典型的感染途径是用污染的食物摄入细菌。在这项研究中,通过PCR检查了从波兰的肉制品和加工环境中收集的153个单核细胞增生性杆菌分离株的基因组中的13个毒力相关基因。所有分离株都拥有来自LIPI-1-hly的基因，acta,plcA,plcB和mpl-以及四个内部蛋白：inla，inlb,inlC,inlj.入侵相关蛋白iap，以及prfA和sigB基因，编码调节蛋白，在所有分离物中也检测到。基因FlaA,编码鞭毛蛋白，在113（74％）分离株中检测到。这是唯一没有在所有分离物中检测到的基因，因为它的存在是血清型依赖性的。基因actA在PCR扩增子中显示具有较长和较短变体的多态性。两个分离株的特征在于截短的inlB基因，序列中缺少141bp，基因测序证实了这一点。所有分离株溶血试验均为阳性,证明了功能性PrfA和Hly蛋白的合成。在分离株\'集合中区分了基于actA多态性的四种基因型和基于inlB多态性的两种基因型。
