Genomic characterization and epidemiological insights into a blaNDM-1-harboring Citrobacter portucalensis strain isolated from hospital wastewater in China.
Yawen Zhang, Qiao Li, Fang He, Wenping Lin, Juan Xu, Yan Yu
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引用次数: 0
Abstract
Objectives: Citrobacter portucalensis is an emerging pathogen of growing clinical and environmental concern. Here, we report the genomic features of a carbapenem-resistant C. portucalensis strain carrying the blaNDM-1 gene on an IncHI2A-IncHI2-RepA plasmid, isolated from the wastewater of a tertiary hospital in China.
Methods: Antimicrobial susceptibility testing was performed using the VITEK2 Gram-negative card and broth microdilution per CLSI guidelines. Illumina NovaSeq short reads and Nanopore MinION long reads were jointly used for sequencing, and hybrid assembly was generated with Unicycler (v0.4.7). MLST, plasmid replicon typing, and ARG detection were conducted using Pathogenwatch and ABRicate (v1.0.1). Phylogenetic analysis of CRNMS3 alongside 52 publicly available C. portucalensis genomes was conducted using a core-genome single-nucleotide polymorphism (SNP)-based approach.
Results: The CRNMS3 genome comprises a chromosome and a 364,750 bp multidrug-resistant plasmid harboring blaNDM-1. The strain displays broad β-lactam and carbapenem resistance and carries 12 antimicrobial resistance genes, most of which, including blaNDM-1, are plasmid-encoded. Among 52 globally identified blaNDM-1-positive C. portucalensis genomes, the majority were from China, spanning multiple sequence types, with ST677 being the most prevalent. Phylogenomic analysis revealed close genomic relatedness between human and environmental isolates within some ST677 strains, indicating potential ongoing transmission across ecological reservoirs.
Conclusion: In summary, we report a blaNDM-1-carrying C. portucalensis strain isolated from hospital wastewater in China and analyze the global prevalence of blaNDM-1 positive C. portucalensis, highlighting its potential for environmental dissemination and the urgent need for coordinated measures to curb blaNDM-1 spread.
期刊介绍：
The Journal of Global Antimicrobial Resistance (JGAR) is a quarterly online journal run by an international Editorial Board that focuses on the global spread of antibiotic-resistant microbes.
JGAR is a dedicated journal for all professionals working in research, health care, the environment and animal infection control, aiming to track the resistance threat worldwide and provides a single voice devoted to antimicrobial resistance (AMR).
Featuring peer-reviewed and up to date research articles, reviews, short notes and hot topics JGAR covers the key topics related to antibacterial, antiviral, antifungal and antiparasitic resistance.
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