Department of Clinical Laboratory, First Medical Center, Chinese People's Liberation Army General Hospital, 100853 Beijing, China.
Department of Microbiology Laboratory, Beijing Chaoyang District Center for Disease Control and Prevention, 100021 Beijing, China.
Front Biosci (Landmark Ed). 2024 Mar 19;29(3):112. doi: 10.31083/j.fbl2903112.
With the recent evolution of multidrug-resistant strains, the genetic characteristics of foodborne serovar Enteritidis and clinical isolates have changed. ST11 is now the most common genotype associated with . Enteritidis isolates.
A total of 83 strains of . Enteritidis were collected at the General Hospital of the People's Liberation Army. Of these, 37 were from aseptic sites in patients, 11 were from the feces of patients with diarrhea, and the remaining 35 were of chicken-origin. The minimum inhibitory concentration of . Enteritidis was determined by the broth microdilution method. Genomic DNA was extracted using the QiAamp DNA Mini Kit, and whole-genome sequencing (WGS) was performed using an Illumina X-ten platform. Prokka was used for gene prediction and annotation, and bioinformatic analysis tools included Resfinder, ISFinder, Virulence Factor Database, and PlasmidFinder. IQ-TREE was used to build a maximum likelihood phylogenetic tree. The phylogenetic relationship and distribution of resistance genes was displayed using iTOL. Comparative population genomics was used to analyze the phenotypes and genetic characteristics of antibiotic resistance in clinical and chicken-origin isolates of . Enteritidis.
The chicken-origin . Enteritidis isolates were more resistant to antibiotics than clinical isolates, and had a broader antibiotic resistance spectrum and higher antibiotic resistance rate. A higher prevalence of antibiotic-resistance genes was observed in chicken-origin . Enteritidis compared to clinical isolates, along with distinct patterns in the contextual characteristics of these genes. Notably, genes such as and were exclusive to plasmids in clinical . Enteritidis, whereas in chicken-origin . Enteritidis they were found in both plasmids and chromosomes. Additionally, was significantly more prevalent in chicken-origin isolates than in clinical isolates. Careful analysis revealed that the delayed isolation of chicken-origin . Enteritidis contributes to accelerated gene evolution. Of note, certain resistance genes tend to integrate seamlessly and persist steadfastly within the chromosome, thereby expediting the evolution of resistance mechanisms against antibiotics. Our comparative analysis of virulence genes in . Enteritidis strains from various sources found no substantial disparities in the distribution of other virulence factors. In summary, we propose that chicken-origin . Enteritidis has the potential to cause clinical infections. Moreover, the ongoing evolution and dissemination of these drug-resistant genes poses a formidable challenge to clinical treatment.
Constant vigilance is needed to monitor the dynamic patterns of drug resistance in . Enteritidis strains sourced from diverse origins.
随着近年来耐药菌株的出现，食源血清型肠炎沙门氏菌的遗传特征和临床分离株已经发生了变化。ST11 现在是与肠炎沙门氏菌分离株相关的最常见基因型。
本研究共收集了中国人民解放军总医院的 83 株肠炎沙门氏菌。其中，37 株来自无菌部位的患者，11 株来自腹泻患者的粪便，其余 35 株来自鸡肉。采用肉汤微量稀释法测定肠炎沙门氏菌的最低抑菌浓度。使用 QiAamp DNA Mini Kit 提取基因组 DNA，采用 Illumina X-ten 平台进行全基因组测序（WGS）。使用 Prokka 进行基因预测和注释，生物信息学分析工具包括 Resfinder、ISFinder、毒力因子数据库和 PlasmidFinder。使用 IQ-TREE 构建最大似然系统发育树。使用 iTOL 显示耐药基因的遗传关系和分布。比较群体基因组学用于分析临床和鸡肉来源的肠炎沙门氏菌分离株的抗生素耐药表型和遗传特征。
鸡肉来源的肠炎沙门氏菌分离株比临床分离株对抗生素的耐药性更强，具有更广泛的抗生素耐药谱和更高的抗生素耐药率。鸡肉来源的肠炎沙门氏菌分离株中耐药基因的检出率高于临床分离株，且这些基因的上下文特征存在明显差异。值得注意的是，临床肠炎沙门氏菌中的 和 等基因仅存在于质粒上，而在鸡肉来源的肠炎沙门氏菌中，这些基因既存在于质粒上，也存在于染色体上。此外， 在鸡肉来源的分离株中更为常见。仔细分析发现，鸡肉来源的肠炎沙门氏菌的分离延迟导致了基因进化的加速。值得注意的是，某些耐药基因倾向于在染色体上无缝整合并稳定存在，从而加速了抗生素耐药机制的进化。我们对不同来源的肠炎沙门氏菌菌株的毒力基因进行了比较分析，发现其他毒力因子的分布没有显著差异。综上所述，我们提出鸡肉来源的肠炎沙门氏菌有可能引起临床感染。此外，这些耐药基因的不断进化和传播对临床治疗构成了严峻挑战。
需要持续监测不同来源的肠炎沙门氏菌菌株的耐药动态模式。
