identifier: traitmech:000250 label: Eleos system definition: A phage defense system in which an organism possesses an Eleos locus represented by LeoA, LeoB, LeoBC, and LeoC profiles that can protect bacteria from bacteriophage infection. definition_source: DOI:10.1016/j.chom.2022.09.017 trait_category: GENOMICS term_kind: CLASS mapping_status: PROPOSED parent_traits: - traitmech:000209 synonyms: - synonym_text: Eleos synonym_type: EXACT_SYNONYM source: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/List_system_article.md evidence: - reference: DOI:10.1016/j.chom.2022.09.017 snippet: discovery of 21 defense systems that protect bacteria from phages, based on computational genomic analyses and phage-infection experiments notes: Millman et al. report the computational and experimental cohort that DefenseFinder cites for Eleos as a bacterial anti-phage system. - reference: DOI:10.1101/2022.05.11.491447 snippet: discovery of 21 new defense systems that protect bacteria from phages, based on computational genomic analyses and phage infection experiments notes: The bioRxiv version of Millman et al. independently carries the 21-system discovery claim linked from DefenseFinder's Eleos article registry. - reference: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/List_system_article.md snippet: Eleos | 10\.1101/2022\.05\.11\.491447 | An expanding arsenal of immune systems that protect bacteria from phages notes: The DefenseFinder model registry maps the named Eleos system to the Millman et al. antiphage-system discovery preprint. - reference: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/DefenseFinder_rules.tsv snippet: "Eleos\tEleos\t2\t2\tEleos__LeoA, Eleos__LeoB, Eleos__LeoBC, Eleos__LeoC" notes: The DefenseFinder rules table models Eleos as a two-gene system over LeoA, LeoB, LeoBC, and LeoC mandatory-profile choices. - reference: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/Liste_hmm_system.md snippet: Eleos__LeoA | Eleos__LeoA | Eleos notes: The DefenseFinder HMM inventory records LeoA as an Eleos profile. - reference: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/Liste_hmm_system.md snippet: Eleos__LeoA2 | Eleos__LeoA2 | Eleos notes: The DefenseFinder HMM inventory records an additional LeoA profile for Eleos. - reference: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/Liste_hmm_system.md snippet: Eleos__LeoB | Eleos__LeoB | Eleos notes: The DefenseFinder HMM inventory records LeoB as an Eleos profile. - reference: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/Liste_hmm_system.md snippet: Eleos__LeoBC | Eleos__LeoBC | Eleos notes: The DefenseFinder HMM inventory records LeoBC as an Eleos profile. - reference: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/Liste_hmm_system.md snippet: Eleos__LeoC | Eleos__LeoC | Eleos notes: The DefenseFinder HMM inventory records LeoC as an Eleos profile. causal_graphs: - graph_id: eleos_locus_restricts_phage title: Eleos loci confer bacterial phage defense description: Conservative system-level sketch linking possession of an Eleos locus to restricted bacteriophage propagation without asserting the unresolved phage trigger or molecular output. scope_status: NONMECHANISTIC scope_notes: The graph captures Eleos as a named anti-phage system with DefenseFinder LeoA, LeoB, LeoBC, and LeoC profiles while leaving its phage trigger, molecular substrate, antiviral effector output, and subtype breadth unresolved. nodes: - node_id: eleos_locus label: Eleos locus node_type: GENETIC_ELEMENT description: An Eleos anti-phage defense locus satisfying a two-profile DefenseFinder rule over LeoA, LeoB, LeoBC, and LeoC profiles. - node_id: restricted_phage_propagation label: restricted phage propagation node_type: BIOLOGICAL_PROCESS description: Reduced propagation of bacteriophage in cells carrying the Eleos system. - node_id: eleos_system_trait label: Eleos system node_type: TRAIT grounding: traitmech:000250 description: Possession of a genome-encoded Eleos 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: eleos_locus predicate: contributes to predicate_id: RO:0002326 object: restricted_phage_propagation description: DefenseFinder maps Eleos to a bacterial anti-phage-system discovery preprint and represents Eleos loci through LeoA, LeoB, LeoBC, and LeoC component profiles. evidence: - reference: DOI:10.1016/j.chom.2022.09.017 snippet: discovery of 21 defense systems that protect bacteria from phages notes: Millman et al. describe the anti-phage discovery cohort that the DefenseFinder Eleos registry row maps to the Eleos system. - reference: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/List_system_article.md snippet: Eleos | 10\.1101/2022\.05\.11\.491447 | An expanding arsenal of immune systems that protect bacteria from phages notes: The DefenseFinder registry maps Eleos itself to the Millman et al. bacterial antiphage-system discovery preprint. - reference: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/DefenseFinder_rules.tsv snippet: "Eleos\tEleos\t2\t2\tEleos__LeoA, Eleos__LeoB, Eleos__LeoBC, Eleos__LeoC" notes: The DefenseFinder rules table supports LeoA, LeoB, LeoBC, and LeoC as Eleos system profile choices. - subject: restricted_phage_propagation predicate: confers predicate_id: METPO:2007700 object: eleos_system_trait description: Eleos-mediated phage restriction realizes the Eleos system trait. evidence: - reference: DOI:10.1016/j.chom.2022.09.017 snippet: discovery of 21 defense systems that protect bacteria from phages notes: Millman et al. place the Eleos discovery cohort in the set of bacterial systems that protect against phages. - reference: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/List_system_article.md snippet: Eleos | 10\.1101/2022\.05\.11\.491447 | An expanding arsenal of immune systems that protect bacteria from phages notes: DefenseFinder records Eleos as a named system from the Millman et al. antiphage discovery preprint. - subject: eleos_system_trait predicate: is a predicate_id: rdfs:subClassOf object: phage_defense_system description: Eleos system possession is a phage-defense-system trait. evidence: - reference: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/List_system_article.md snippet: An expanding arsenal of immune systems that protect bacteria from phages notes: DefenseFinder associates Eleos with the Millman et al. bacterial antiphage-system discovery paper. discussions: - discussion_id: eleos-mechanism-gap prompt: Resolve Eleos phage triggers and effector outputs before minting narrower Eleos mechanism children. kind: KNOWLEDGE_GAP status: OPEN rationale: Millman et al. and DefenseFinder support Eleos as a named anti-phage system with LeoA, LeoB, LeoBC, and LeoC profiles, but the trigger, molecular substrate, antiviral effector output, and subtype-specific mechanism are not resolved enough here to assert a narrower mechanistic child trait. attaches_to: - causal_graphs#eleos_locus_restricts_phage posed_by: codex posed_date: '2026-09-18' curation_history: - timestamp: '2026-09-18T20:38:41Z' curator: codex action: MINTED_TRAITMECH_ID changes: Minted Eleos system as a DOI-backed GENOMICS TraitRecord under phage defense system after an ignored-and-hidden duplicate review found no exact live TraitMech, METPO, or prior proposal record; the replacement placeholder is reserved in proposals/metpo_traitmech_v127. llm_assisted: true