Zhang Weili, Xu Hao, Li Yaling, Liu Ruishan, Lou Danfeng
Department of Laboratory Medicine, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China; State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Zhejiang Provincial Key Laboratory for Drug Clinical Research and Evaluation, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China.
State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Zhejiang Provincial Key Laboratory for Drug Clinical Research and Evaluation, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China.
J Glob Antimicrob Resist. 2024 Dec;39:209-211. doi: 10.1016/j.jgar.2024.09.006. Epub 2024 Oct 20.
In this study we report the complete genome sequence of a hypervirulent ST65 Klebsiella pneumoniae isolate harbouring mcr-8 from China. The aim was to investigate its molecular characteristics and resistance mechanisms.
Colistin-resistant hypervirulent K. pneumonia was isolated from an in-patient in China. The entire genome was sequenced on the Illumina NovaSeq 6000 System and long-read ONT Platform. De novo assembly was conducted using SPAdes and Unicycler. S1 nuclease pulsed-field gel electrophoresis, Southern blot, and antimicrobial susceptibility testing were performed. Sequence type, antimicrobial resistance, and virulence-related genes were predicted from the sequence. Circular maps of multiple plasmid comparisons were drawn by the BLAST Ring Image.
The complete genome sequence of K. pneumoniae ACESH00926 consists of one chromosome and two plasmids. ACESH00926 belongs to K2 ST65 according to multilocus sequence typing. ACESH00926 also showed high resistance to colistin (MIC >8 µg/mL). Several ARGs were identified, including the mobile colistin-resistant gene, mcr-8, which was located in an IncFIl(K)/IncFIA(HI1)-type plasmid. The larger plasmid was a pK244-like virulence plasmid that carries a series of virulence genes, such as regulators of the mucoid phenotype (rmpA and rmpA2), salmochelin siderophore biosynthesis (iroB), ABC transporter (iroC), ferric aerobactin receptor (iutA), aerobactin siderophore biosynthesis protein (iucC), and aerobactin synthetase (iucA)-encoded genes, in addition to another plasmid carrying mcr-8 with a conserved genetic context (dgkA-sasA-copR-mcr-8-ccdA-ccdB-xerD-repE-parM-umuC-lexA-klcA).
The necessity of monitoring a combination of colistin-resistant and hypervirulent K. pneumoniae strains in the future is emphasised in this article.
在本研究中，我们报告了一株来自中国的携带mcr-8的高毒力ST65肺炎克雷伯菌分离株的全基因组序列。目的是研究其分子特征和耐药机制。
从中国一名住院患者中分离出对黏菌素耐药的高毒力肺炎克雷伯菌。使用Illumina NovaSeq 6000系统和长读长ONT平台对整个基因组进行测序。使用SPAdes和Unicycler进行从头组装。进行了S1核酸酶脉冲场凝胶电泳、Southern印迹和抗菌药物敏感性测试。从序列中预测序列类型、抗菌药物耐药性和毒力相关基因。通过BLAST环形图像绘制多个质粒比较的环形图。
肺炎克雷伯菌ACESH00926的全基因组序列由一条染色体和两个质粒组成。根据多位点序列分型，ACESH00926属于K2 ST65。ACESH00926对黏菌素也表现出高耐药性（MIC>8μg/mL）。鉴定出了几个耐药基因，包括位于IncFIl(K)/IncFIA(HI1)型质粒中的可移动黏菌素耐药基因mcr-8。较大的质粒是一种类似pK244的毒力质粒，除了另一个携带mcr-8且具有保守遗传背景（dgkA-sasA-copR-mcr-8-ccdA-ccdB-xerD-repE-parM-umuC-lexA-klcA）的质粒外，还携带一系列毒力基因，如黏液样表型调节因子（rmpA和rmpA2）、沙门菌素铁载体生物合成（iroB）、ABC转运蛋白（iroC）、铁载体气杆菌素受体（iutA）、气杆菌素铁载体生物合成蛋白（iucC）和气杆菌素合成酶（iucA）编码基因。
本文强调了未来监测黏菌素耐药和高毒力肺炎克雷伯菌菌株组合的必要性。
