{
  "abstract": "Proteolytic processing is typically used to reveal post-translational modifications for mass spectrometric analysis. Here, we show that proteolysis of ubiquitinated proteins additionally generates a chemically addressable diglycine remnant that can be enzymatically remodeled. We exploit the ability of sortase to recognize ubiquitin-derived diglycine motifs as nucleophiles and ligate functionalized LPXTG peptides directly onto ubiquitin-remnant peptides. This reaction enables installation of a biotin affinity handle on defined ubiquitinated substrates and peptides derived from mammalian cell lysates, including lysine- and N-terminal ubiquitination. The resulting branched conjugates generate characteristic fragment ions that facilitate their identification. We further develop a bifunctional sortase donor containing an internal trypsin cleavage site, enabling affinity capture followed by conversion of enriched ubiquitin sites into a compact TGG mass-spectrometric signature. Alternatively, reversible sortase chemistry can regenerate the original diglycine-containing peptide. These studies establish ubiquitin-derived proteolytic remnants as latent chemical handles that can be converted into modular affinity and analytical tags, providing an antibody-independent approach to interrogating protein ubiquitination.",
  "abstract_shown": true,
  "affiliations": [
    "University of Pennsylvania"
  ],
  "article_type": "New results",
  "arxiv": null,
  "author_total": 5,
  "authors": [
    {
      "name": "N. Raniszewski"
    },
    {
      "name": "K. Beckley"
    },
    {
      "name": "J. Hintzen"
    },
    {
      "name": "M. Noel"
    },
    {
      "affs": [
        0
      ],
      "name": "G. Burslem"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/cr533qngkx7g8.bib",
  "cited_by": 0,
  "doi": "10.64898/2026.06.29.735432",
  "fulltext_url": "https://www.biorxiv.org/content/10.64898/2026.06.29.735432v2.full",
  "id": "cr533qngkx7g8",
  "issns": [],
  "landing_url": "https://www.biorxiv.org/content/10.64898/2026.06.29.735432v2",
  "language": null,
  "licence": "CC-BY-ND",
  "licence_label": "CC BY-ND",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nd/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "biorxiv",
      "biochemistry"
    ],
    [
      "openalex",
      "1312|Ubiquitin and proteasome pathways"
    ]
  ],
  "openalex": "W7166826350",
  "pdf_url": "https://www.biorxiv.org/content/10.64898/2026.06.29.735432v2.full.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-06-29",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/cr533qngkx7g8.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:23:26Z",
      "native_id": "10.64898/2026.06.29.735432",
      "source": "biorxiv",
      "url": "https://www.biorxiv.org/content/10.64898/2026.06.29.735432v2"
    }
  ],
  "subjects": [
    {
      "field": "biochemistry",
      "origin": "openalex:1312|Ubiquitin and proteasome pathways",
      "subfield": "molecular-biology"
    }
  ],
  "title": "Ubiquitin-Derived Diglycine Remnants as Chemical Handles for Chemoenzymatic Proteomics",
  "title_text": "Ubiquitin-Derived Diglycine Remnants as Chemical Handles for Chemoenzymatic Proteomics",
  "type": "preprint",
  "updated_at": "2026-10-30T12:23:26Z",
  "url": "https://research.draconitic.com/paper/cr533qngkx7g8",
  "venue": "bioRxiv",
  "versions": []
}