{
  "abstract": "DarTG defense systems studied to date contain a DarT1 or DarT2 toxin that blocks phage replication by ADP-ribosylating DNA and a NADAR or macrodomain antitoxin, DarG, that reverses this modification at homeostasis. Here, we identify additional DarTG subfamilies, one of which comprises a DarT3 toxin, an ADP-ribosylhydrolase (ARH)-domain antitoxin, and a helicase family protein, DarH. The Escherichia coli DarHTG3 system confers broad phage defense, requires DarH and, unlike previously characterized DarTG systems, modifies adenine. Characterization of additional DarH-containing DarTG systems reveals that a subset also target guanine. Our data support a model in which ADP-bound DarH functions as a processivity factor by recruiting DarT to its single-stranded DNA substrate and allowing for ADP-ribosylation of multiple target sites. These findings reveal how a helicase family protein regulates an antiviral effector by promoting DNA engagement rather than unwinding and thereby expanding the functional repertoire of helicase family proteins in bacterial immunity.",
  "abstract_shown": true,
  "affiliations": [
    "Washington University in St Louis School of Medicine"
  ],
  "article_type": "New results",
  "arxiv": null,
  "author_total": 13,
  "authors": [
    {
      "name": "T. Griesman"
    },
    {
      "name": "A. Q. Arifah"
    },
    {
      "name": "E. J. Tomko"
    },
    {
      "name": "Y. Tan"
    },
    {
      "name": "N. Tsao"
    },
    {
      "name": "J. T. Trotter"
    },
    {
      "name": "S. S. Khochare"
    },
    {
      "name": "N. A. Carlson"
    },
    {
      "name": "N. Mosammaparast"
    },
    {
      "name": "D. Zhang"
    },
    {
      "name": "E. A. Galburt"
    },
    {
      "name": "C. Patinios"
    },
    {
      "affs": [
        0
      ],
      "name": "M. LeRoux"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/7yv8zrrkyjy6k.bib",
  "cited_by": 0,
  "doi": "10.64898/2026.11.02.763693",
  "fulltext_url": "https://www.biorxiv.org/content/10.64898/2026.11.02.763693v1.full",
  "id": "7yv8zrrkyjy6k",
  "issns": [],
  "landing_url": "https://www.biorxiv.org/content/10.64898/2026.11.02.763693v1",
  "language": null,
  "licence": "CC-BY-NC",
  "licence_label": "CC BY-NC",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nc/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "biorxiv",
      "microbiology"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://www.biorxiv.org/content/10.64898/2026.11.02.763693v1.full.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-11-02",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/7yv8zrrkyjy6k.ris",
  "sources": [
    {
      "first_seen": "2026-11-04T12:21:00Z",
      "native_id": "10.64898/2026.11.02.763693",
      "source": "biorxiv",
      "url": "https://www.biorxiv.org/content/10.64898/2026.11.02.763693v1"
    }
  ],
  "subjects": [
    {
      "field": "biology",
      "origin": "biorxiv:microbiology",
      "subfield": "microbiology"
    }
  ],
  "title": "Helicase family proteins promote antiviral ADP-ribosylation of DNA purines",
  "title_text": "Helicase family proteins promote antiviral ADP-ribosylation of DNA purines",
  "type": "preprint",
  "updated_at": "2026-11-05T00:21:10Z",
  "url": "https://research.draconitic.com/paper/7yv8zrrkyjy6k",
  "venue": "bioRxiv",
  "versions": []
}