Zhang Huan, Dong Su, Mao Caiping, Fang Yuejuan, Ying Junjie
Department of Clinical Laboratory, Zhejiang Cancer Hospital, Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, Zhejiang, China.
Department of Clinical Laboratory, Shaoxing Hospital of Traditional Chinese Medicine Affiliated to Zhejiang Chinese Medical University, Shaoxing, Zhejiang, China.
Front Cell Infect Microbiol. 2025 Mar 31;15:1565980. doi: 10.3389/fcimb.2025.1565980. eCollection 2025.
This study aimed to characterize the genomes of two rare ST592 isolates and to explore their evolution into carbapenem-resistant hypervirulent (CR-hvKp).
The minimum inhibitory concentrations (MICs) were determined using a VITEK 2 compact system. Conjugation experiments were conducted using film matings. Whole-genome sequencing (WGS) was performed using the Illumina and Nanopore platforms. The antimicrobial resistance determinants were identified using the ABRicate program in the ResFinder database. Insertion sequences were identified using ISFinder and the bacterial virulence factors identified using the Virulence Factor Database (VFDB). The K and O loci were examined using Kleborate. Multilocus sequence typing (MLST) and replicon type identification were performed by the Center for Genomic Epidemiology. Conjugation-related elements were predicted using finder. The plasmid structure was visualized using Circos, and a possible evolutionary model was constructed using BioRender.
Isolates KPZM6 and KPZM16 were identified as ST592 and KL57, respectively, and were collected from the same department. The antimicrobial susceptibility testing data revealed that KPZM16 possesses an extensively drug-resistant (XDR) profile, whereas KPZM6 is a susceptible . The hybrid assembly showed that both KPZM6 and KPZM16 have one pLVPK-like virulence plasmid carrying the , , and gene clusters. However, strain KPZM16 harbors one IncN plasmid carrying the carbapenem resistance genes , , and . The results of the conjugation experiments demonstrated that the plasmid could be transferred to the recipient strain. It is possible that the NDM-1-producing plasmid was transferred from KPZM6 to KPZM16 via conjugation, leading to the formation of CR-hvKp.
This is the first study in which complete genomic characterization of the rare NDM-1-producing ST592 clinical isolate was performed. This study provides a possible evolutionary hypothesis for the formation of CR-hvKp via conjugation. Early detection is recommended to avoid the extensive spread of this clone.
本研究旨在对两株罕见的ST592分离株的基因组进行特征分析，并探讨它们向耐碳青霉烯类高毒力（CR-hvKp）菌株的进化过程。
使用VITEK 2 compact系统测定最低抑菌浓度（MIC）。通过薄膜交配进行接合实验。使用Illumina和Nanopore平台进行全基因组测序（WGS）。使用ResFinder数据库中的ABRicate程序鉴定抗菌药物耐药决定簇。使用ISFinder鉴定插入序列，并使用毒力因子数据库（VFDB）鉴定细菌毒力因子。使用Kleborate检测K和O位点。由基因组流行病学中心进行多位点序列分型（MLST）和复制子类型鉴定。使用finder预测接合相关元件。使用Circos可视化质粒结构，并使用BioRender构建可能的进化模型。
分离株KPZM6和KPZM16分别被鉴定为ST592和KL57，且均来自同一科室。抗菌药物敏感性测试数据显示，KPZM16具有广泛耐药（XDR）特征，而KPZM6为敏感菌株。混合组装显示，KPZM6和KPZM16均有一个携带、和基因簇的pLVPK样毒力质粒。然而，菌株KPZM16含有一个携带碳青霉烯类耐药基因、和的IncN质粒。接合实验结果表明，该质粒可转移至受体菌株。产NDM-1的质粒有可能通过接合从KPZM6转移至KPZM16，导致CR-hvKp的形成。
这是首次对罕见的产NDM-1的ST592临床分离株进行完整基因组特征分析的研究。本研究为通过接合形成CR-hvKp提供了一种可能的进化假说。建议进行早期检测以避免该克隆的广泛传播。
