Genomic characterization, antimicrobial resistance and virulence profiles of Klebsiella pneumoniae isolated from mink in Northern China.

Klebsiella pneumoniae is an important opportunistic pathogen of One Health concern, and its multidrug-resistant (MDR) and hypervirulent strains pose serious threats to public health. However, the epidemiological characteristics, antimicrobial resistance profiles, and virulence potential of K. pneumoniae circulating in farmed minks remain poorly understood. In this study, we integrated phenotypic antimicrobial susceptibility testing, whole-genome sequencing, and metagenomic analysis to investigate the epidemiology, resistance determinants, and virulence characteristics of K. pneumoniae isolated from farmed minks in northern China. A total of 41 K. pneumoniae strains from 325 fecal samples (isolation rate: 12.62%), including three hypervirulent strains. All isolates exhibited multidrug resistance, with complete resistance to florfenicol, azithromycin, and sulfisoxazole, but remained highly susceptible to carbapenems and polymyxin B. Whole-genome sequencing revealed that the isolates harbored 241 antibiotic resistance genes (ARGs), including ESBL-associated genes and the plasmid-mediated mcr-1.1, along with 7111 virulence factor genes (VFGs) and 135 mobile genetic elements (MGEs). Metagenomic analysis further revealed a complex resistome and virulome, with 7259 ARGs and 6701 virulence-related genes identified across samples. Antibiotic target alteration and efflux were the dominant resistance mechanisms, while effector delivery systems, metabolic functions, and adherence were the major virulence categories. MGEs were abundant, especially transposases, indicating active genetic mobility within the microbial community. Overall, this study provides a comprehensive characterization of antimicrobial resistance and virulence features of mink-derived K. pneumoniae and highlights the potential role of farmed minks as reservoirs of multidrug-resistant bacteria within the One Health framework, offering important insights for antimicrobial resistance surveillance and public health risk assessment.