中国畜牧兽医 ›› 2025, Vol. 52 ›› Issue (12): 5956-5966.doi: 10.16431/j.cnki.1671-7236.2025.12.039

• 基础兽医 • 上一篇    

1株携带多黏菌素耐药基因mcr-1的多重耐药大肠杆菌全基因组测序及分析

杨璟珂, 杨思婕, 刘冉, 张铁, 王春光   

  1. 河北农业大学动物医学院, 保定 071001
  • 收稿日期:2025-03-25 发布日期:2025-11-28
  • 通讯作者: 张铁, 王春光 E-mail:zhangtie1998@163.com;wcg9566@163.com
  • 作者简介:杨璟珂,E-mail:969690863@qq.com。
  • 基金资助:
    国家自然科学基金(32473072);河北省现代农业产业技术体系专项资金(HBCT2024240207、HBCT2024250206)

Whole-genome Sequencing and Analysis of a Multidrug-resistant Escherichia coli Strain Carrying Polymyxin Resistance Gene mcr-1

YANG Jingke, YANG Sijie, LIU Ran, ZHANG Tie, WANG Chunguang   

  1. College of Veterinary Medicine, Hebei Agricultural University, Baoding 071001, China
  • Received:2025-03-25 Published:2025-11-28

摘要: 【目的】了解临床分离的大肠杆菌的耐药性和毒力,为后续禽大肠杆菌病的临床防治提供参考。【方法】本研究通过菌体形态学观察和分子生物学手段对临床分离的1株鸡源病原菌进行分离纯化鉴定,通过药敏试验了解分离菌株的耐药性,利用Illumina NovaSeq 测序平台对分离菌株进行全基因组测序。【结果】分离菌株在麦康凯琼脂培养基上呈现粉红色圆形、光滑的菌落,镜检为革兰阴性杆菌,16S rDNA测序结果显示,与GenBank数据库已登录的大肠杆菌(登录号:NR_024570.1)相似性>98%,经mcr-1基因特异性引物PCR扩增发现,分离的大肠杆菌携带多黏菌素耐药基因mcr-1。药敏试验结果显示,该分离菌株对青霉素类、头孢菌素类、氨基糖苷类、多肽类等12类抗菌药耐药,仅对氯霉素和米诺环素敏感,表现为多重耐药;分离菌株基因组总长为5 057 884 bp;基于KEGG、COG、GO、CAZy等数据库的基因功能注释分析表明,该菌株具备完整的氨基酸转运系统、细胞增殖与分化机制以及代谢功能;通过与CARD和VFDB数据库比对发现,该菌株具有效应器分泌系统、鞭毛、脑内皮侵袭素等毒力基因,且该菌株携带氨基糖苷类、磺胺类、喹诺酮类、肽类、四环素类和β-内酰胺类等多种抗菌药物的耐药基因,这些基因使该菌株表现出较强的毒力与多重耐药性。【结论】本研究分离获得1株鸡源携带mcr-1基因的大肠杆菌,具有多重耐药性与高毒力特征,其基因组结构与环境适应能力共同促成了其强致病性。本研究结果为禽大肠杆菌病的预防和治疗提供了一定的数据参考。

关键词: 大肠杆菌; 全基因组测序; 基因功能注释; 耐药性

Abstract: 【Objective】 This experiment was conducted to investigate the antimicrobial resistance and virulence of clinically isolated Escherichia coli (E.coli),provided insights for the prevention and treatment of avian colibacillosis. 【Method】 In this study,a chicken-derived clinical isolate was purified and identified by morphological observation and molecular biology methods.Its antimicrobial susceptibility was determined by drug sensitivity test,and the whole-genome was sequenced using the Illumina NovaSeq platform. 【Result】 The isolated strain formed pink,round and smooth colonies on MacConkey agar,and microscopic examination revealed Gram-negative bacilli.16S rDNA sequencing showed over 98% similarity with E.coli (accession No.:NR_024570.1) in GenBank database.PCR amplification using mcr-1 gene-specific primers revealed that the isolated E.coli carried the polymyxin resistance gene mcr-1.Antimicrobial susceptibility test demonstrated that the isolate was resistant to twelve classes of antimicrobials,including penicillins,cephalosporins,aminoglycosides and polypeptides,etc.,exhibiting multidrug resistance.The complete genome size was 5 057 884 bp.Functional annotation analysis based on KEGG,COG,GO and CAZy databases demonstrated that the strain possessed complete amino acid transport systems,cell proliferation and differentiation mechanisms,and metabolic functions.Comparative analysis with CARD and VFDB databases identified virulence genes encoding effector secretion systems,flagella and brain endothelial invasins.Moreover,the strain carried multiple antimicrobial resistance genes against aminoglycosides,sulfonamides,quinolones,peptides,tetracyclines and β-lactams,contributing to its high virulence and multidrug resistance. 【Conclusion】 In this study,a chicken-derived Escherichia coli isolate carrying the mcr-1 gene was obtained,exhibiting multidrug resistance and high virulence.Its genomic structure and environmental adaptability collectively contributed to its strong pathogenicity.The findings provided valuable data for the prevention and treatment of avian colibacillosis.

Key words: Escherichia coli; whole-genome sequencing; gene functional annotation; antimicrobial resistance

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