{
  "id": 8155724,
  "title": "Species-specific metabolic networks shape evolutionary routes to functional rescue",
  "url": "https://urgent.news/2026/09/17/species-specific-metabolic-networks-shape-evolutionary-routes-to",
  "topic": "science",
  "section": "Science",
  "published": "2026-09-17T00:00:00.000Z",
  "source": {
    "name": "bioRxiv",
    "slug": "biorxiv",
    "url": "https://www.biorxiv.org/content/10.64898/2026.09.15.751699v1?rss=1"
  },
  "original_language": "en",
  "account": "Metabolic networks are intricate webs of interconnected pathways, but it remains uncertain how organism- and environment-specific factors influence their ability to evolve under metabolic stress or if these processes follow general principles. To investigate this, researchers examined metabolic evolvability in Bacillus subtilis by utilizing auxotrophic mutants that lack central biosynthetic enzymes. These mutants were subjected to two genetic backgrounds with differing biofilm-forming capacities and subjected to direct or gradual selection through nutrient gradients.\n\nUnder these conditions, B. subtilis was able to bypass nine out of seventeen essential functions. Notably, rescue was more frequent in the biofilm-proficient background and under gradual selection. This difference was also associated with a higher number of mutations in coding regions, particularly nonsynonymous ones. During adaptation, the process proceeded through loss-of-function mutations that alleviated regulatory or enzymatic constraints and redirected metabolic flux.\n\nWhen compared to Escherichia coli, substantial differences in bypassability and genetic routes were observed, even under matched conditions. However, it was found that two cross-species solutions converged at the pathway level. The data suggest that species-specific metabolic networks shape the available rescue routes, while ecological context influences their evolutionary accessibility during adaptation.",
  "summary": "Metabolic networks are highly interconnected. Still, it remains unclear whether organism- and environment-specific factors shape their capacity to evolve in response to metabolic stress or whether it follows general principles. Here, we studied metabolic evolvability in Bacillus subtilis using auxotrophic mutants lacking central biosynthetic enzymes. Across two genetic backgrounds with…",
  "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."
}