Genomic and phenotypic characterization of antimicrobial resistance in clinical Nocardia species isolates

作者：Ziyu Song, Bingqian Du, Min Yuan, Jirao Shen, Shuai Xu, Wanchun Guan, Binghuai Lu, Zhenjun Li · 发表于：Frontiers in Cellular and Infection Microbiology · 年份：2025 · DOI：10.3389/fcimb.2025.1672889 · 被引用次数：10 · 研究领域：Actinomycetales infections and treatment、Mycorrhizal Fungi and Plant Interactions、Genomics and Phylogenetic Studies

Background Antimicrobial resistance is prevalent across Nocardia species, with varying resistance profiles among different species, which poses significant challenges to effective treatment strategies. Our study aimed to assess the antimicrobial susceptibility profiles of various Nocardia species and investigate the potential correlation between resistance phenotypes and their underlying genotypes. Methods This study analyzed 148 clinical Nocardia isolates from 13 provinces in China. Minimum inhibitory concentrations (MICs) for 15 antimicrobial agents were determined using the microbroth dilution method. Whole genome sequencing (WGS) was performed for all isolates, followed by bioinformatics analyses integrated with 70 human-sourced Nocardia genomes in the National Center for Biotechnology Information (NCBI), encompassing species verification, phylogenetic analysis, and the identification of antimicrobial resistance genes (ARGs). Results Average Nucleotide Identity (ANI) analysis reclassified several misidentified isolates and revealed 14 potentially novel Nocardia species, underscoring the taxonomic complexity within this genus. Nocardia species exhibited distinct resistance profiles: Nocardia farcinica demonstrated elevated resistance to cephalosporins and tobramycin; Nocardia otitidiscaviarum showed broad resistance to β -lactams and quinolones; and Nocardia cyriacigeorgica exhibited resistance to quinolones, cefepime, and cefoxitin. Notably, clarithromycin resistance was ...