{
  "abstract": "Quorum sensing in Gram-positive bacteria commonly relies on posttranslationally modified peptide pheromones. In Bacillus subtilis, the prenyltransferase ComQ catalyzes tryptophan prenylation of the quorum-sensing peptide ComX, but the structural basis of this unique peptide modification has remained unclear. Here we identified a previously uncharacterized ComQ homolog, StheQ, and its cognate peptide substrate, StheX, from Sphaerobacter thermophilus and investigated their structural and functional relationship. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis demonstrated that StheQ catalyzes prenylation of the tryptophan residue located second from the C-terminus of StheX. Crystal structures of apo StheQ and its complexes with a farnesyl pyrophosphate analog revealed that StheQ adopts the all--helical fold of the trans-isoprenyl diphosphate synthase (IPPS) superfamily while possessing an active-site architecture adapted for peptide-based indole prenylation. The structures identified a single Mg2+-binding site associated with the first aspartic acid-rich motif and showed no evidence for metal coordination at the pseudo-second aspartic acid-rich motif. Site-directed mutagenesis, complex formation assays, and docking analyses identified a peptide-binding pocket adjacent to the active site and suggested that N215 contributes to productive positioning of the acceptor tryptophan. These findings establish the structural basis for peptide prenylation by a ComQ-family enzyme, providing insight into the evolution of peptide-based indole prenylation within the IPPS superfamily, and support the view that ComQ-family enzymes constitute a distinct functional branch specialized for peptide modification.",
  "abstract_shown": true,
  "affiliations": [
    "Kitasato University"
  ],
  "article_type": "New results",
  "arxiv": null,
  "author_total": 11,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "T. Matsui"
    },
    {
      "name": "S. Inoue"
    },
    {
      "name": "S. Yanagimoto"
    },
    {
      "name": "A. Kaneko"
    },
    {
      "name": "R. Tago"
    },
    {
      "name": "A. Suto"
    },
    {
      "name": "M. Odagi"
    },
    {
      "name": "Y. Kodera"
    },
    {
      "name": "H. Morita"
    },
    {
      "name": "I. Abe"
    },
    {
      "name": "M. Okada"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/by2exvweg12w3.bib",
  "cited_by": 0,
  "doi": "10.64898/2026.08.29.745113",
  "fulltext_url": "https://www.biorxiv.org/content/10.64898/2026.08.29.745113v1.full",
  "id": "by2exvweg12w3",
  "issns": [],
  "landing_url": "https://www.biorxiv.org/content/10.64898/2026.08.29.745113v1",
  "language": null,
  "licence": "CC-BY-NC-ND",
  "licence_label": "CC BY-NC-ND",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "biorxiv",
      "biochemistry"
    ],
    [
      "openalex",
      "1312|Bacterial biofilms and quorum sensing"
    ]
  ],
  "openalex": "W7204785593",
  "pdf_url": "https://www.biorxiv.org/content/10.64898/2026.08.29.745113v1.full.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-08-29",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/by2exvweg12w3.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:30Z",
      "native_id": "10.64898/2026.08.29.745113",
      "source": "biorxiv",
      "url": "https://www.biorxiv.org/content/10.64898/2026.08.29.745113v1"
    }
  ],
  "subjects": [
    {
      "field": "biochemistry",
      "origin": "openalex:1312|Bacterial biofilms and quorum sensing",
      "subfield": "molecular-biology"
    }
  ],
  "title": "Identification and structural basis of a Chloroflexus protein with homology to Bacillus quorum sensing-related prenyltransferase",
  "title_text": "Identification and structural basis of a Chloroflexus protein with homology to Bacillus quorum sensing-related prenyltransferase",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:30Z",
  "url": "https://research.draconitic.com/paper/by2exvweg12w3",
  "venue": "bioRxiv",
  "versions": []
}