{
  "id": 12923334,
  "title": "Gfa, a new integron-borne fosfomycin resistance family",
  "url": "https://urgent.news/2026/10/08/gfa-a-new-integron-borne-fosfomycin-resistance-family",
  "topic": "science",
  "section": "Science",
  "published": "2026-10-08T00:00:00.000Z",
  "source": {
    "name": "bioRxiv",
    "slug": "biorxiv",
    "url": "https://www.biorxiv.org/content/10.64898/2026.10.07.757220v1?rss=1"
  },
  "original_language": "en",
  "account": "Fosfomycin, a widely used antibiotic for treating multidrug-resistant Gram-negative infections, is increasingly facing resistance challenges. Current resistance surveillance methods heavily depend on detecting known fos genes through homology-based techniques. However, a novel fosfomycin resistance determinant, Gfa, has been identified through functional screening of 129 integron gene cassettes, marking a significant discovery.\n\nGfa exhibits its resistance prowess across Enterobacterales and Pseudomonas aeruginosa, conferring high-level fosfomycin resistance. Distinct from the typical Fos enzymes, Gfa possesses a conserved cysteine-rich, zinc-organized architecture, which remains resilient even under phosphonoformate inhibition. This architectural feature is crucial for Gfa's activity and sets it apart from the conventional enzymes.\n\nUsing crude-extract assays, researchers have confirmed that Gfa inactivates fosfomycin under metal-chelating conditions, reliant on the presence of glutathione. Remarkably, distant Gfa homologs also display resistance, although their activity is limited, confining the resistance to a specific subset of tested proteins.\n\nThese findings collectively reveal Gfa as a previously unknown fosfomycin resistance family, emphasizing the need for more comprehensive methods beyond homology-based mining. This approach uncovers novel resistance determinants and sheds light on predicting the functional capabilities of various family members.",
  "summary": "Fosfomycin is increasingly used to treat multidrug-resistant Gram-negative infections, yet resistance surveillance largely relies on homology-based detection of known fos genes. Here, we identify Gfa, a previously unrecognized integron-borne fosfomycin resistance determinant uncovered through functional screening of 129 integron gene cassettes. Gfa confers high-level fosfomycin resistance across…",
  "key_points": [],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}