NCU04302: ProtNLM2 function review

Source method: ProtNLM2. Source version: live API snapshot 2026-09-09T03:00:51.831347+00:00. Accession: Q1K772. Raw source: NCU04302-protnlm-source.json.

Exact emitted paragraph

Accepts the ubiquitin from the E1 complex and catalyzes its covalent attachment to other proteins

Atomic claims

Exact claim span Assessment Rationale
Accepts the ubiquitin from the E1 complex PLI (0) The Ubc9 subfamily accepts activated SUMO. The literal ubiquitin substrate specifies the wrong E2 subfamily.
catalyzes its covalent attachment to other proteins PLI (0) “its” refers to ubiquitin in the emitted sentence. Ubc9 catalyzes SUMO attachment, so the stated substrate-specific reaction is incorrect.

The conserved E2 reaction pattern is plausible only after changing the modifier to SUMO; that correction is not silently substituted for the original claim. The generic transferase GO prediction is separately LSP.

Evidence and provenance

Modifier-specific sequence assignments are “DR CDD; cd23798; UBCc_UBE2I; 1.” and “DR FunFam; 3.10.110.10:FF:000035; SUMO-conjugating enzyme ubc9; 1.” Full-length comparisons give 75.0% identity to fission-yeast Ubc9 and 62.42% to human Ubc9, compared with 42.0% to the recorded ubiquitin-E2 donor; reproducible results preserve all alignments and controls. PMID:12597774 directly characterizes SUMO transfer in the fission-yeast reference. The current GOA PAINT assertion at PANTHER:PTN000629675 places the target in the SUMO E2 lineage; PROSITE identifies a UBC core at residues 3–156 and an active-site cysteine at 92. PMID:9435231(https://pubmed.ncbi.nlm.nih.gov/9435231/) establishes recombinant yeast and mammalian Ubc9 thioesters with SUMO. This is a conserved-family inference for the target, not an NCU04302 biochemical assay. The recorded phmmer donor is Arabidopsis UBC2 (P42745), and its current reviewed function text is identical to the emitted paragraph; that record attributes ubiquitin conjugation to PMID:16339806. This exact textual agreement does not establish the internal mechanism of prediction. The preserved donor record confirms that this is a different E2 specificity, not simply a synonym for SUMO.

Error type: PARALOG_OVERANNOTATION. Donor record: NCU04302-donor-P42745.json.

Complete paragraph evidence object

{
  "commentType": "FUNCTION",
  "texts": [
    {
      "evidences": [
        {
          "evidenceCode": "ECO:0008006",
          "id": "ProtNLM2",
          "properties": [
            {
              "key": "model_score",
              "value": "0.19"
            },
            {
              "key": "phmmer_accession",
              "value": "P42745"
            },
            {
              "key": "phmmer_score",
              "value": "127.9"
            }
          ],
          "source": "Google"
        }
      ],
      "value": "Accepts the ubiquitin from the E1 complex and catalyzes its covalent attachment to other proteins"
    }
  ]
}