Saved in:
Bibliographic Details
Main Authors: Kieffer, Nicolas, Böhm, Maria-Elisabeth, Berglund, Fanny, Marathe, Nachiket P, Gillings, Michael R, Larsson, D G Joakim
Format: Artículo científico
Language:en
Published: Journal of global antimicrobial resistance 2025
Subjects:
Online Access:https://pubmed.ncbi.nlm.nih.gov/39725324/
Tags: Add Tag
No Tags, Be the first to tag this record!
Table of Contents:
  • Identification of novel FosX family determinants from diverse environmental samples. Kieffer, Nicolas Böhm, Maria-Elisabeth Berglund, Fanny Marathe, Nachiket P Gillings, Michael R Larsson, D G Joakim Fosfomycin Phylogeny Escherichia coli Anti-Bacterial Agents Drug Resistance, Bacterial Wastewater India Geologic Sediments Antarctic Regions Integrons Microbial Sensitivity Tests Metagenomics Bacterial Proteins This study aimed to identify novel fosfomycin resistance genes across diverse environmental samples, ranging in levels of anthropogenic pollution. We focused on fosfomycin resistance, and given its increasing clinical importance, explored the prevalence of these genes within different environmental contexts. Metagenomic DNA was extracted from wastewater and sediment samples collected from sites in India, Sweden, and Antarctica. Class 1 integron gene cassette libraries were prepared, and resistant clones were selected on fosfomycin-supplemented media. Long-read sequencing was performed followed by bioinformatics analysis to identify novel fosfomycin resistance genes. The genes were cloned and functionally characterized in E. coli, and the impact of phosphonoformate on the enzymes was assessed. Four novel fosfomycin resistance genes were identified. Phylogenetic analysis placed these genes within the FosX family, a group of metalloenzymes that hydrolyse fosfomycin without thiol conjugation. The genes were subsequently renamed fosE2, fosI2, fosI3, and fosP. Functional assays confirmed that these genes conferred resistance to fosfomycin in E. coli, with MIC ranging from 32 μg/ml to 256 μg/ml. Unlike FosA/B enzymes, these FosX-like proteins were resistant to phosphonoformate inhibitory action. A fosI3 homolog was identified in Pseudomonas aeruginosa, highlighting potential clinical relevance. This study expands the understanding of fosfomycin resistance by identifying new FosX family members across diverse environments. The lack of phosphonoformate inhibition underscores the clinical importance of these poorly studied enzymes, which warrant further investigation, particularly in pathogenic contexts.