Mai Zifeng, Wei Lusan, Shi Chunlei, Zhan Zeqiang
State Key Laboratory of Microbial Metabolism, Department of Food Science & Technology, School of Agriculture & Biology, Shanghai Jiao Tong University, Shanghai 200240, China.
College of Plant Protection, South China Agricultural University, Guangzhou 510642, China.
Foods. 2025 Aug 22;14(17):2933. doi: 10.3390/foods14172933.
is a major foodborne pathogen that poses an increasing threat due to the emergence of -mediated colistin resistance. However, data on -positive in pork products are limited. In this study, 457 samples collected in 2023 from pig slaughterhouses in Guangdong province were investigated to determine the prevalence and genomic characteristics of -positive isolates. We found that 92 isolates (20.1%, 92/457) were recovered, representing six serotypes, including ( = 29) and Rissen ( = 29). High resistance to tetracycline (90.2%, 83/92) and multidrug resistance (58.7%, 54/92) were observed. Critically, two colistin-resistant ST198 isolates (2.2%) harboring on transferable IncI2 plasmids were identified. Genomic analysis revealed a novel multidrug resistance region (MRR, ~57 kb) inserted into the locus (containing , , , and ) and a variant Genomic Island 1 (SGI1-KI, containing , , and ) in these isolates. The MRR and SGI1-KI may enhance bacterial survival under antibiotic selection pressure. Phylogenetic analysis showed close relatedness to human clinical strains, suggesting food chain transmission. The findings highlight a high antimicrobial resistance burden, the emergence of transferable last-resort colistin resistance (), and acquisition of complex resistance determinants (MRR, SGI1-KI), underscoring an urgent need for enhanced "One Health" surveillance.
是一种主要的食源性病原体，由于介导的对粘菌素的耐药性出现，其构成的威胁日益增加。然而，关于猪肉产品中阳性的数据有限。在本研究中，对2023年从广东省生猪屠宰场采集的457份样本进行了调查，以确定阳性分离株的流行情况和基因组特征。我们发现共分离出92株分离株（20.1%，92/457），代表六种血清型，包括（=29）和里森（=29）。观察到对四环素的高耐药性（90.2%，83/92）和多重耐药性（58.7%，54/92）。至关重要的是，鉴定出两株携带可转移IncI2质粒上的粘菌素耐药分离株ST198（2.2%）。基因组分析揭示了一个插入位点（包含、、、和）的新型多重耐药区域（MRR，约57 kb）以及这些分离株中的一个变异基因组岛1（SGI1-KI，包含、、和）。MRR和SGI1-KI可能会增强细菌在抗生素选择压力下的生存能力。系统发育分析表明与人类临床菌株密切相关，表明存在食物链传播。这些发现突出了高抗菌药物耐药负担、可转移的最后手段粘菌素耐药性（）的出现以及复杂耐药决定因素（MRR，SGI1-KI）的获得，强调迫切需要加强“同一健康”监测。
