identifier: METPO:1005014
label: methyl red test positive
definition: A phenotype in which an organism tests positive in the methyl red test,
  indicating mixed acid fermentation.
trait_category: OTHER
term_kind: CLASS
mapping_status: SEEDED
parent_traits:
- METPO:1005013
synonyms:
- synonym_text: methyl red test
  synonym_type: RELATED_SYNONYM
  source: metpo.owl
curation_history:
- timestamp: '2026-09-12T19:14:16Z'
  curator: seed_from_metpo
  action: SEEDED_FROM_METPO
  changes: imported from data/raw/metpo.owl (CLASS)
- timestamp: '2026-09-12T19:16:03Z'
  curator: codex
  action: ENRICHED_FROM_LITERATURE
  changes: Added the METPO methyl-red-test-positive phenotype with stable-URL and
    DOI-backed methyl-red-test evidence after a repository-wide duplicate review covering
    ignored and hidden files.
  llm_assisted: true
- timestamp: '2026-09-12T19:34:17Z'
  curator: codex
  action: CURATION_REVIEW_REVISION
  changes: 'Resolved PR #862 review issues #863 and #864 by removing a flattened Hansen
    Table 3 row from evidence snippets and narrowing the Hansen ASM Manual evidence
    note to match its quote.'
  llm_assisted: true
- timestamp: '2026-09-12T20:15:55Z'
  curator: codex
  action: RESOLVED_PARENT_GAP
  changes: Reparented methyl red test positive below the newly curated METPO:1005013
    methyl red test assay parent and marked the temporary assay-parent discussion
    resolved.
  llm_assisted: true
- timestamp: '2026-09-12T20:44:24Z'
  curator: codex
  action: CURATION_REVIEW_REVISION
  changes: Moved the methyl-red parent-gap closure into resolution_note and resolved_date
    so the original non-assay parent rationale remains visible.
  llm_assisted: true
definition_source: https://asm.org/getmedia/40946f85-9357-4563-aa8a-994427efa825/Methyl-Red-and-Voges-Proskauer-Test-Protocols.pdf
evidence:
- reference: https://asm.org/getmedia/40946f85-9357-4563-aa8a-994427efa825/Methyl-Red-and-Voges-Proskauer-Test-Protocols.pdf
  snippet: When the culture medium turns red after addition of methyl red, because
    of a pH at or below 4.4 from the fermentation of glucose, the culture has a positive
    result for the MR test (Fig.1A).
  notes: The ASM protocol PDF defines a positive methyl-red-test readout as red culture
    medium after methyl red is added, reflecting glucose fermentation that acidifies
    the medium to pH 4.4 or lower.
- reference: DOI:10.1128/JCM.42.8.3665-3669.2004
  snippet: 'In the ASM Manual of Clinical Microbiology, only 6 of the 18 biochemical
    tests used in the present investigation are listed for Klebsiella species: indole,
    MR, VP, LDC, ODC, and malonate'
  notes: Hansen et al. evaluated methyl red as a conventional Klebsiella biochemical
    test listed in the ASM Manual of Clinical Microbiology.
canonical_examples:
- taxon_id: NCBITaxon:54291
  taxon_label: Klebsiella ornithinolytica
  note: Hansen et al. Table 3 reported 100.0% methyl-red-positive results for K. ornithinolytica
    across the CPHL, NRL, and SSI reference laboratories.
  reference: DOI:10.1128/JCM.42.8.3665-3669.2004
discussions:
- discussion_id: methyl-red-test-positive-assay-parent-gap
  prompt: Resolve a non-assay parent for positive methyl-red-test phenotypes before
    narrowing parent_traits below phenotype.
  kind: CURATION_TODO
  status: RESOLVED
  rationale: METPO:1005013 is the seeded superclass of METPO:1005014, but METPO:1005013
    defines an assay rather than a broader microbial trait class, so this record is
    temporarily parented directly to METPO:1000059 phenotype.
  posed_by: codex
  posed_date: '2026-09-12'
  resolved_date: '2026-09-12'
  resolution_note: METPO:1005013 is now represented as the seeded methyl-red-test
    assay parent, so this assay-outcome phenotype can use its exact source superclass
    instead of a temporary direct phenotype parent; this resolves the exact METPO
    assay-parent gap, not the broader non-assay parent question for assay-outcome
    phenotypes.