{
  "id": 14976399,
  "title": "The Phage Time Continuum: Genome Organization Constrains Anti-CRISPR Success",
  "url": "https://urgent.news/2026/10/16/the-phage-time-continuum-genome-organization-constrains-anti-crispr",
  "topic": "science",
  "section": "Science",
  "published": "2026-10-16T00:00:00.000Z",
  "source": {
    "name": "bioRxiv",
    "slug": "biorxiv",
    "url": "https://www.biorxiv.org/content/10.64898/2026.10.15.759504v1?rss=1"
  },
  "original_language": "en",
  "account": "Bacteria and phages engage in an evolutionary arms race, with bacterial defenses like CRISPR-Cas combating viral anti-defenses such as anti-CRISPR (Acr) systems. A team of researchers investigated whether CRISPR-Cas and Acr systems interact in a timing-dependent genetic conflict. If Acr genes do not act early enough during infection, they may fail to neutralize CRISPR; meanwhile, CRISPR-Cas may not locate its target in time, allowing Acr to neutralize it. As phages typically inject their genomes in a linear fashion, the position of the genome along the sequence can serve as a proxy for the time elapsed since the onset of infection. The researchers propose that phage genomes containing Acr systems will display a unique pattern of CRISPR spacers compared to those without, reflecting the time-dependent interaction between the two organisms. This interaction has been dubbed the Phage Time Continuum. In a study of 1,462 phage genomes and 105 mobile plasmid genomes infecting Pseudomonas aeruginosa, the researchers found that CRISPR spacers were significantly more prevalent in genomes containing Acr systems than in those with other anti-defense systems from either phages or plasmids. Additionally, in genomes containing Acr, CRISPR spacers were mapped to earlier positions along the genome, suggesting that success in neutralizing the Acr systems depends not only on targeting specific genes but also on the precise location of the spacers within the genome.",
  "summary": "Bacteria and lytic phages experience antagonistic co-evolution, with bacterial defenses (e.g., CRISPR-Cas) battling phage anti-defenses (e.g., anti-CRISPR (Acr) systems). We investigate whether CRISPR-Cas and Acr engage in a timing-dependent genetic conflict. If anti-CRISPR genes act too late in infection, they risk failing to neutralize CRISPR, if Cas cannot find its target in time, Acr may be…",
  "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."
}