Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agri-food Safety and Quality, Ministry of Agriculture of China, Yangzhou University, China; Jiangsu Key Lab of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety, Yangzhou University, China.
Nantong Center for Disease Control and Prevention, Nantong, China.
Food Res Int. 2022 Apr;154:111007. doi: 10.1016/j.foodres.2022.111007. Epub 2022 Feb 22.
Salmonella enterica serovar Rissen is recognized as one of the most common serotypes in pigs and pig products in many countries and can be transmitted to human through the consumption of contaminated food. To reveal the genetic characteristics of S. Rissen, 39 isolates from human and animal food were subjected to whole-genome sequencing analysis combined with 337 genome sequences downloaded from the NCBI Assembly database. Core genome single nucleotide polymorphism (cgSNP) divided these S. Rissen isolates into two clusters, of which cluster A included 78.3% of American isolates, while cluster B was mainly composed of isolates from China, Asia, and the UK. The 39 S. Rissen isolates located in cluster B were further divided into two subclusters with cluster B-1 of 26 isolates from both humans and food, while cluster B-2 consisted of 13 isolates from animal food, mainly pork. CRISPR typing and cgMLST of the 39 isolates showed perfect correspondence to cgSNP results of their phylogenetic relationship. Virulence factors analysis revealed that ABZJ_0085 and ABZJ_0086 genes presenting in cluster B-2 were lost in cluster B-1. Additionally, antimicrobial resistance gene profiles showed qnrS1, cmlA1, and tet(M) could be detected in cluster B-2 other than cluster B-1. The findings of the divergent difference between cluster B-1 and cluster B-2 demonstrated that S. Rissen was continuously evolved through the pork production chain. In conclusion, pigs are the main reservoir for S. Rissen capable of causing human nontyphoid salmonellosis.
里森沙门氏菌血清型是许多国家猪和猪产品中最常见的血清型之一，可通过食用污染食物传播给人类。为了揭示里森沙门氏菌的遗传特征，对 39 株来自人和动物食品的分离株进行了全基因组测序分析，并结合从 NCBI 组装数据库下载的 337 个基因组序列。核心基因组单核苷酸多态性（cgSNP）将这些里森沙门氏菌分离株分为两个聚类，其中聚类 A 包含 78.3%的美国分离株，而聚类 B 主要由来自中国、亚洲和英国的分离株组成。聚类 B 中的 39 株里森沙门氏菌分离株进一步分为两个亚聚类，其中聚类 B-1 由来自人和食物的 26 株组成，而聚类 B-2 由来自动物食品的 13 株组成，主要是猪肉。39 株里森沙门氏菌的 CRISPR 分型和 cgMLST 与它们的系统发育关系的 cgSNP 结果完全一致。毒力因子分析显示，聚类 B-2 中存在的 ABZJ_0085 和 ABZJ_0086 基因在聚类 B-1 中丢失。此外，抗生素耐药基因谱显示，除了聚类 B-1 外，还可以在聚类 B-2 中检测到 qnrS1、cmlA1 和 tet(M)。聚类 B-1 和聚类 B-2 之间的差异表明，里森沙门氏菌通过猪肉生产链不断进化。总之，猪是引起人类非伤寒沙门氏菌病的里森沙门氏菌的主要储存宿主。
