identifier: traitmech:000521 label: Brc217 system definition: A phage defense system in which an organism possesses a gcu217/Brc217 bacteriophage-resistance integron cassette that supports growth during bacteriophage challenge. definition_source: DOI:10.1126/science.ads0915 trait_category: GENOMICS term_kind: CLASS mapping_status: PROPOSED parent_traits: - traitmech:000209 synonyms: - synonym_text: gcu217 synonym_type: RELATED_SYNONYM source: DOI:10.1126/science.ads0915 - synonym_text: brc217 synonym_type: RELATED_SYNONYM source: DOI:10.1126/science.ads0915 evidence: - reference: DOI:10.1126/science.ads0915 snippet: brc217 L 97.6 44.2 96.6 56.5 notes: Manual transcription of the Supplementary Fig. S2 Brc217 low-MOI E. coli IJ1862 heatmap row; the visible cells show reduced inhibition, including 97.6% for P1, 44.2% for phi80, 96.6% for HK544, and 56.5% for F13. - reference: DOI:10.1126/science.ads0915 snippet: brc217 H 91.2 96.7 notes: Manual transcription of the Supplementary Fig. S2 Brc217 high-MOI E. coli IJ1862 heatmap row; the visible cells show reduced inhibition, including 91.2% for HK544 and 96.7% for F13. - reference: DOI:10.1126/science.ads0915 snippet: defense profiles of identified Bacteriophage Resistance integron Cassettes (BRiCs) against a panel of different phages notes: Kieffer et al. classify positive integron cassettes as BRiCs and compare their defense profiles across a phage panel. - reference: DOI:10.1126/science.ads0915 snippet: 'brc113 brc217 brc76 brcWGS21 brc22 brc23' notes: Kieffer et al. include brc217 among identified BRiCs with predicted attC secondary structures. - reference: https://www.science.org/doi/suppl/10.1126/science.ads0915/suppl_file/science.ads0915_sm.pdf snippet: 'C934 pMBA brc217 E. coli IJ1862' notes: Kieffer et al.'s supplementary construct table lists pMBA brc217 in E. coli IJ1862 for high/low-MOI phage-panel testing. - reference: DOI:10.1126/science.ads0915 snippet: 'C940 pMBA brc217 K. pneumoniae KP5' notes: Kieffer et al.'s supplementary construct table lists the pMBA brc217 plasmid introduced into Klebsiella pneumoniae KP5. causal_graphs: - graph_id: brc217_integron_cassette_confers_phage_resistance title: Brc217 BRiCs confer phage resistance description: Conservative system-level sketch linking a gcu217/Brc217 bacteriophage-resistance integron cassette to phage resistance and Brc217 system possession. scope_status: NONMECHANISTIC scope_notes: The graph captures Brc217 at the integron-cassette and phage-resistance-output level without asserting the native host range, exact sensitive-phage breadth outside the reported panels, direct molecular substrate, or a DefenseFinder article/HMM/rules profile absent from the pinned snapshot. nodes: - node_id: brc217_integron_cassette label: Brc217 integron cassette node_type: GENETIC_ELEMENT description: A mobile integron gene cassette named by the gcu217 source key and curated as Brc217. - node_id: brc217_phage_resistance label: Brc217 phage resistance node_type: BIOLOGICAL_PROCESS description: Reduced phage inhibition in cells carrying the gcu217/Brc217 integron cassette. - node_id: brc217_system_trait label: Brc217 system node_type: TRAIT grounding: traitmech:000521 description: Possession of a genome-encoded Brc217 phage-defense system. - node_id: phage_defense_system label: phage defense system node_type: TRAIT grounding: traitmech:000209 description: Possession of one or more genome-encoded immune systems that inhibit bacteriophage infection. edges: - subject: brc217_integron_cassette predicate: contributes to predicate_id: RO:0002326 object: brc217_phage_resistance description: The gcu217/Brc217 integron cassette contributes to phage resistance during phage-panel assays. evidence: - reference: DOI:10.1126/science.ads0915 snippet: brc217 L 97.6 44.2 96.6 56.5 notes: Manual transcription of the Supplementary Fig. S2 Brc217 low-MOI E. coli IJ1862 heatmap row; the visible cells show reduced inhibition, including 97.6% for P1, 44.2% for phi80, 96.6% for HK544, and 56.5% for F13. - reference: DOI:10.1126/science.ads0915 snippet: brc217 H 91.2 96.7 notes: Manual transcription of the Supplementary Fig. S2 Brc217 high-MOI E. coli IJ1862 heatmap row; the visible cells show reduced inhibition, including 91.2% for HK544 and 96.7% for F13. - subject: brc217_phage_resistance predicate: confers predicate_id: METPO:2007700 object: brc217_system_trait description: Brc217-linked phage resistance realizes the Brc217 system possession trait. evidence: - reference: DOI:10.1126/science.ads0915 snippet: brc217 L 97.6 44.2 96.6 56.5 notes: Manual transcription of the Supplementary Fig. S2 Brc217 low-MOI E. coli IJ1862 heatmap row; the visible cells show reduced inhibition, including 97.6% for P1, 44.2% for phi80, 96.6% for HK544, and 56.5% for F13. - reference: DOI:10.1126/science.ads0915 snippet: brc217 H 91.2 96.7 notes: Manual transcription of the Supplementary Fig. S2 Brc217 high-MOI E. coli IJ1862 heatmap row; the visible cells show reduced inhibition, including 91.2% for HK544 and 96.7% for F13. - reference: DOI:10.1126/science.ads0915 snippet: defense profiles of identified Bacteriophage Resistance integron Cassettes (BRiCs) against a panel of different phages notes: Kieffer et al. classify positive integron cassettes as BRiCs and compare their defense profiles across a phage panel. - subject: brc217_system_trait predicate: is a predicate_id: rdfs:subClassOf object: phage_defense_system description: Brc217 system possession is a phage-defense-system trait. evidence: - reference: DOI:10.1126/science.ads0915 snippet: defense profiles of identified Bacteriophage Resistance integron Cassettes (BRiCs) against a panel of different phages notes: Kieffer et al. classify positive integron cassettes as BRiCs and compare their defense profiles across a phage panel. - reference: DOI:10.1126/science.ads0915 snippet: 'brc113 brc217 brc76 brcWGS21 brc22 brc23' notes: Kieffer et al. include brc217 among identified BRiCs with predicted attC secondary structures. discussions: - discussion_id: brc217-defensefinder-model-gap prompt: Resolve Brc217 native host breadth, exact sensitive-phage breadth, molecular output, and DefenseFinder article/HMM/rules coverage before minting narrower Brc217 mechanism children. kind: KNOWLEDGE_GAP status: OPEN rationale: Kieffer et al. identify brc217 as a bacteriophage-resistance integron cassette. The pinned DefenseFinder article registry, HMM inventory, and rules table have no exact gcu217 or Brc217 row, so the first-pass record leaves native-host breadth, profile boundaries, exact phage target breadth, and direct molecular output unresolved. evidence: - reference: DOI:10.1126/science.ads0915 snippet: brc217 L 97.6 44.2 96.6 56.5 notes: Manual transcription of the Supplementary Fig. S2 Brc217 low-MOI E. coli IJ1862 heatmap row; the visible cells show reduced inhibition, including 97.6% for P1, 44.2% for phi80, 96.6% for HK544, and 56.5% for F13. - reference: DOI:10.1126/science.ads0915 snippet: brc217 H 91.2 96.7 notes: Manual transcription of the Supplementary Fig. S2 Brc217 high-MOI E. coli IJ1862 heatmap row; the visible cells show reduced inhibition, including 91.2% for HK544 and 96.7% for F13. - reference: DOI:10.1126/science.ads0915 snippet: defense profiles of identified Bacteriophage Resistance integron Cassettes (BRiCs) against a panel of different phages notes: Kieffer et al. classify positive integron cassettes as BRiCs and compare their defense profiles across a phage panel. - reference: DOI:10.1126/science.ads0915 snippet: 'brc113 brc217 brc76 brcWGS21 brc22 brc23' notes: Kieffer et al. include brc217 among identified BRiCs with predicted attC secondary structures. - reference: DOI:10.1126/science.ads0915 snippet: 'C940 pMBA brc217 K. pneumoniae KP5' notes: Kieffer et al. list brc217 in the heterologous Klebsiella pneumoniae KP5 BRiC panel. - reference: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/List_system_article.md notes: A structured first-pass search of the pinned DefenseFinder article registry found no exact gcu217, brc217, or Brc217 row. - reference: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/Liste_hmm_system.md notes: A structured first-pass search of the pinned DefenseFinder HMM inventory found no exact gcu217, brc217, or Brc217 row. - reference: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/DefenseFinder_rules.tsv notes: A structured first-pass search of the pinned DefenseFinder rules table found no exact gcu217, brc217, or Brc217 system row. attaches_to: - causal_graphs#brc217_integron_cassette_confers_phage_resistance posed_by: codex posed_date: '2026-10-01' curation_history: - timestamp: '2026-10-01T17:54:02Z' curator: codex action: MINTED_TRAITMECH_ID changes: Minted Brc217 system as a DOI-backed GENOMICS TraitRecord under phage defense system after an ignored-and-hidden duplicate review found no exact live TraitMech, METPO, history, or prior proposal record; kept the graph at BRiC integron-cassette level because the pinned DefenseFinder article registry, HMM inventory, and rules table have no exact Brc217 row; the replacement placeholder is reserved in proposals/metpo_traitmech_v398. llm_assisted: true - timestamp: '2026-10-01T17:54:03Z' curator: codex action: REVIEW_CANONICAL_EXAMPLE_EVIDENCE_GAP changes: Reviewed Brc217 system during initial curation and left canonical_examples empty because the sources support heterologous gcu217/Brc217 phage-resistance assays but not a direct named native microbial isolate exemplar with experimentally verified endogenous Brc217 activity. No paid research was used. llm_assisted: true