identifier: traitmech:000159
label: alpha-chymotrypsin activity
definition: A physiological enzyme-activity phenotype in which a cell exhibits chymotrypsin-like
  serine endopeptidase activity, preferentially cleaving peptide bonds on the carboxyl
  side of tyrosine, tryptophan, phenylalanine, or leucine residues.
definition_source: https://iubmb.qmul.ac.uk/enzyme/EC3/4/21/1.html
trait_category: PHYSIOLOGY
term_kind: CLASS
mapping_status: PROPOSED
parent_traits:
- METPO:1000059
synonyms:
- synonym_text: alpha-chymotrypsin
  synonym_type: RELATED_SYNONYM
  source: DOI:10.1099/ijsem.0.006017
evidence:
- reference: https://iubmb.qmul.ac.uk/enzyme/EC3/4/21/1.html
  snippet: '<b>Reaction:</b> Preferential cleavage: Tyr<img src="../../../EZgif/FISS.GIF"
    align=top>, Trp<img src="../../../EZgif/FISS.GIF" align=top>, Phe<img src="../../../EZgif/FISS.GIF"
    align=top>, Leu<img src="../../../EZgif/FISS.GIF" align=top>'
  notes: The NC-IUBMB EC 3.4.21.1 entry accepts the name chymotrypsin and its reaction
    line places the scissile-bond FISS.GIF image immediately after Tyr, Trp, Phe,
    and Leu.
- reference: DOI:10.1099/ijsem.0.006017
  snippet: 'enzymatic activities are present for: α-galactosidase, N-acetyl-β-glucosaminidase,
    arginine arylamidase, proline arylamidase, leucyl glycine arylamidase, phenylalanine
    arylamidase, leucine arylamidase, tyrosine arylamidase, alanine arylamidase, glycine
    arylamidase, histidine arylamidase, glutamyl glutamic acid arylamidase, serine
    arylamidase, valine arylamidase, cysteine arylamidase, esterase, esterase lipase,
    alpha-chymotrypsin'
  notes: Srinivasan et al. listed alpha-chymotrypsin among enzymatic activities present
    in the Amygdalobacter indicium species description, consistent with the positive
    API ZYM table row for both assayed A. indicium strains.
canonical_examples:
- taxon_id: NCBITaxon:3029272
  taxon_label: Amygdalobacter indicium
  note: Srinivasan et al. reported Amygdalobacter indicium as positive for alpha-chymotrypsin
    activity in the API ZYM enzyme activity panel.
  reference: DOI:10.1099/ijsem.0.006017
discussions:
- discussion_id: alpha-chymotrypsin-activity-xref-gap
  prompt: Resolve an exact external ontology class for alpha-chymotrypsin activity
    before adding a TraitRecord xref.
  kind: CURATION_TODO
  status: OPEN
  rationale: GO:0004263 chymotrypsin activity is obsolete, and its replacement GO:0004252
    denotes broader serine-type endopeptidase molecular function rather than the organism-level
    chymotrypsin-like serine endopeptidase phenotype. GO:0004252 is appropriate as
    a causal-node grounding for generic serine-type endopeptidase activity, not as
    an equivalent TraitRecord xref.
  posed_by: codex
  posed_date: '2026-09-12'
curation_history:
- timestamp: '2026-09-12T05:29:03Z'
  curator: codex
  action: MINTED_TRAITMECH_ID
  changes: Minted alpha-chymotrypsin activity as a URL/DOI-backed TraitRecord after
    a repository-wide duplicate review covering ignored and hidden files; METPO has
    no exact alpha-chymotrypsin activity class yet.
  llm_assisted: true
- timestamp: '2026-09-12T05:47:58Z'
  curator: codex
  action: CORRECTED_EVIDENCE_SNIPPET
  changes: Corrected the IUBMB reaction-line snippet for alpha-chymotrypsin activity
    so it preserves the scissile-bond image tags from the source HTML (#819).
  llm_assisted: true
- timestamp: '2026-09-12T06:00:57Z'
  curator: codex
  action: TIGHTENED_DEFINITION_WORDING
  changes: Tightened the alpha-chymotrypsin activity definition to describe a chymotrypsin-like
    organismal phenotype instead of over-specifying production of the named vertebrate
    enzyme (#820).
  llm_assisted: true