identifier: traitmech:000288 label: Ceres system definition: A phage defense system in which an organism possesses a Ceres locus that can protect bacteria from bacteriophage infection. definition_source: DOI:10.1101/2025.01.08.631966 trait_category: GENOMICS term_kind: CLASS mapping_status: PROPOSED parent_traits: - traitmech:000209 synonyms: - synonym_text: Ceres synonym_type: EXACT_SYNONYM source: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/List_system_article.md - synonym_text: CrsA1 synonym_type: RELATED_SYNONYM source: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/Liste_hmm_system.md - synonym_text: CrsA2 synonym_type: RELATED_SYNONYM source: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/Liste_hmm_system.md evidence: - reference: DOI:10.1101/2025.01.08.631966 snippet: Among the remaining eight systems, six demonstrated increased resistance to at least one phage with more than 100 fold reduction in plaque forming units (PFU) (Figure 3a, Supplementary Figure 5). As Streptomyces are mostly soil dwelling bacteria, we named these systems after deities of the soil and earth (Ceres, Geb, Veles, Prithvi, Ukko and Oshun). notes: Mordret et al. directly name Ceres among six Streptomyces systems that increased resistance to at least one phage. - reference: DOI:10.1101/2025.01.08.631966 snippet: The bacterial pangenome encodes an immense array of antiphage systems, yet much of their diversity remains uncharted notes: Mordret et al. motivate a conservative system-level record that does not assert a resolved Ceres trigger, effector output, or universal pathway. - reference: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/List_system_article.md snippet: Ceres | 10\.1101/2025\.01\.08\.631966 | Protein and genomic language models chart a vast landscape of antiphage defenses notes: The DefenseFinder model registry maps the named Ceres system to the Mordret et al. antiphage-system discovery preprint. - reference: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/Liste_hmm_system.md snippet: Ceres__CrsA1 | | Ceres notes: The DefenseFinder HMM inventory records CrsA1 in the Ceres model namespace. - reference: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/Liste_hmm_system.md snippet: Ceres__CrsA2 | | Ceres notes: The DefenseFinder HMM inventory records CrsA2 in the Ceres model namespace. causal_graphs: - graph_id: ceres_locus_restricts_phage title: Ceres loci confer bacterial phage defense description: Conservative system-level sketch linking possession of a Ceres locus to restricted bacteriophage propagation without asserting the unresolved phage trigger or molecular output. scope_status: NONMECHANISTIC scope_notes: The graph captures Ceres as a named anti-phage system with CrsA1 and CrsA2 DefenseFinder HMM profile entries while leaving its phage trigger, molecular substrate, antiviral effector output, and subtype breadth unresolved. nodes: - node_id: ceres_locus label: Ceres locus node_type: GENETIC_ELEMENT description: A Ceres anti-phage defense locus cataloged in DefenseFinder with CrsA1 and CrsA2 HMM profile entries. - node_id: restricted_phage_propagation label: restricted phage propagation node_type: BIOLOGICAL_PROCESS description: Reduced propagation of bacteriophage in cells carrying the Ceres system. - node_id: ceres_system_trait label: Ceres system node_type: TRAIT grounding: traitmech:000288 description: Possession of a genome-encoded Ceres 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: ceres_locus predicate: contributes to predicate_id: RO:0002326 object: restricted_phage_propagation description: DefenseFinder maps Ceres to a protein- and genomic-language-model antiphage-system discovery preprint and catalogs CrsA1 and CrsA2 HMM profile entries in the Ceres model namespace. evidence: - reference: DOI:10.1101/2025.01.08.631966 snippet: Among the remaining eight systems, six demonstrated increased resistance to at least one phage with more than 100 fold reduction in plaque forming units (PFU) (Figure 3a, Supplementary Figure 5). As Streptomyces are mostly soil dwelling bacteria, we named these systems after deities of the soil and earth (Ceres, Geb, Veles, Prithvi, Ukko and Oshun). notes: Mordret et al. directly name Ceres among six Streptomyces systems that restricted at least one phage. - reference: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/List_system_article.md snippet: Ceres | 10\.1101/2025\.01\.08\.631966 | Protein and genomic language models chart a vast landscape of antiphage defenses notes: The DefenseFinder registry maps Ceres itself to the Mordret et al. bacterial antiphage-system discovery preprint. - reference: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/Liste_hmm_system.md snippet: Ceres__CrsA1 | | Ceres notes: The DefenseFinder HMM inventory records CrsA1 in the Ceres model namespace. - reference: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/Liste_hmm_system.md snippet: Ceres__CrsA2 | | Ceres notes: The DefenseFinder HMM inventory records CrsA2 in the Ceres model namespace. - subject: restricted_phage_propagation predicate: confers predicate_id: METPO:2007700 object: ceres_system_trait description: Ceres-mediated phage restriction realizes the Ceres system trait. evidence: - reference: DOI:10.1101/2025.01.08.631966 snippet: Among the remaining eight systems, six demonstrated increased resistance to at least one phage with more than 100 fold reduction in plaque forming units (PFU) (Figure 3a, Supplementary Figure 5). As Streptomyces are mostly soil dwelling bacteria, we named these systems after deities of the soil and earth (Ceres, Geb, Veles, Prithvi, Ukko and Oshun). notes: Mordret et al. directly name Ceres among six systems that increased resistance to at least one phage. - reference: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/List_system_article.md snippet: Ceres | 10\.1101/2025\.01\.08\.631966 | Protein and genomic language models chart a vast landscape of antiphage defenses notes: DefenseFinder records Ceres as a named system from the Mordret et al. antiphage discovery preprint. - subject: ceres_system_trait predicate: is a predicate_id: rdfs:subClassOf object: phage_defense_system description: Ceres system possession is a phage-defense-system trait. evidence: - reference: https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/List_system_article.md snippet: '| Ceres | 10\.1101/2025\.01\.08\.631966 | Protein and genomic language models chart a vast landscape of antiphage defenses |' notes: DefenseFinder associates Ceres with the Mordret et al. bacterial antiphage-system discovery preprint. discussions: - discussion_id: ceres-mechanism-gap prompt: Resolve Ceres phage triggers and effector outputs before minting narrower Ceres mechanism children. kind: KNOWLEDGE_GAP status: OPEN rationale: Mordret et al. and DefenseFinder support Ceres as a named anti-phage system with CrsA1 and CrsA2 HMM profile entries, 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#ceres_locus_restricts_phage posed_by: codex posed_date: '2026-09-19' curation_history: - timestamp: '2026-09-19T18:23:47Z' curator: codex action: MINTED_TRAITMECH_ID changes: Minted Ceres 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_v165. llm_assisted: true