Ishihara Kanako, Someno Suzuka, Matsui Kaoru, Nakazawa Chisato, Abe Takahiro, Harima Hayato, Omatsu Tsutomu, Ozawa Manao, Iwabuchi Eriko, Asai Tetsuo
Laboratory of Veterinary Public Health, Faculty of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu 183-8509, Tokyo, Japan.
Center for Infectious Disease Epidemiology and Prevention Research, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu 183-8509, Tokyo, Japan.
Antibiotics (Basel). 2025 Mar 10;14(3):288. doi: 10.3390/antibiotics14030288.
BACKGROUND/OBJECTIVES: The acquisition of antimicrobial resistance by foodborne pathogens is a serious human health concern. In Japan, combinations of antimicrobial resistance genes in from chicken meat were common among several serovars. Therefore, we hypothesized that different serovars share a common antimicrobial resistance plasmid.
Antimicrobial resistance transfer was tested in . Infantis and . Schwarzengrund, the major serovars used as donors. The plasmid structure was determined by subjecting . Infantis Sal_238 and . Schwarzengrund Sal_249 to short- and long-read sequencing.
The high homology between pSal_249Sch and pSal_238Inf suggests they have a common ancestor. Because the sequences of pSal_238Inf and pSal_249Sch were highly homologous to pESI (a plasmid for emerging Infantis), pSal_238Inf and pSal_249Sch were identified as pESI-like plasmids. . Schwarzengrund is the third serovar to expand its distribution related to pESI-like plasmid acquisition. Core-genome multilocus sequence-type analysis revealed that . Schwarzengrund isolates with pESI-like plasmids from Japan (core-genome sequence-type [cgST] 167363 and cgST287831), the UK (cgST167363), and the USA (cgST167363, cgST196045, and cgST287831) were closely related; they are also suggested to share a common ancestor. The transfer of antimicrobial resistance was observed in combinations of both serovars. Specifically, the tentative plasmid sequence obtained via short-read sequencing, PCR, and conjugation experiments identified deletions of antimicrobial resistance genes (, , and ), class 1 integron, mercury resistance operon, and/or plasmid transfer region in the pESI-like plasmid.
These data on the structural diversity of pESI-like plasmids suggest that some time has passed since . Schwarzengrund acquired them.
背景/目的：食源性病原体获得抗菌药物耐药性是一个严重的人类健康问题。在日本，鸡肉中抗菌药物耐药基因的组合在几种血清型中很常见。因此，我们推测不同血清型共享一个共同的抗菌药物耐药质粒。
在用作供体的主要血清型婴儿沙门氏菌和施瓦岑格伦德沙门氏菌中测试抗菌药物耐药性转移。通过对婴儿沙门氏菌Sal_238和施瓦岑格伦德沙门氏菌Sal_249进行短读长和长读长测序来确定质粒结构。
pSal_249Sch和pSal_238Inf之间的高度同源性表明它们有一个共同的祖先。由于pSal_238Inf和pSal_249Sch的序列与pESI（一种新兴婴儿沙门氏菌的质粒）高度同源，pSal_238Inf和pSal_249Sch被鉴定为pESI样质粒。施瓦岑格伦德沙门氏菌是第三个因获得pESI样质粒而扩大其分布的血清型。核心基因组多位点序列分型分析表明，来自日本（核心基因组序列型[cgST]167363和cgST287831）、英国（cgST167363）和美国（cgST167363、cgST196045和cgST287831）的带有pESI样质粒的施瓦岑格伦德沙门氏菌分离株密切相关；它们也被认为有一个共同的祖先。在两种血清型的组合中都观察到了抗菌药物耐药性的转移。具体而言，通过短读长测序、PCR和接合实验获得的暂定质粒序列确定了pESI样质粒中抗菌药物耐药基因（blaTEM、blaCTX-M和blaSHV）、1类整合子、汞抗性操纵子和/或质粒转移区域的缺失。
这些关于pESI样质粒结构多样性的数据表明，施瓦岑格伦德沙门氏菌获得它们已经过去了一段时间。
