identifier: traitmech:000225 label: AbiQ system definition: An abortive infection system in which an organism possesses an AbiQ type III toxin-antitoxin locus whose protein endoribonuclease and cognate RNA antitoxin module alter early phage mRNA profiles and restrict phage propagation after adsorption. definition_source: DOI:10.1128/JB.00296-13 trait_category: GENOMICS term_kind: CLASS mapping_status: PROPOSED parent_traits: - traitmech:000214 evidence: - reference: DOI:10.1128/AEM.64.12.4748-4756.1998 snippet: the system encoded by pSRQ900 was classified as an abortive infection mechanism and was named AbiQ notes: Emond et al. named AbiQ as a Lactococcus plasmid-encoded abortive infection system rather than an adsorption-blocking or restriction-modification defense. - reference: DOI:10.1128/AEM.64.12.4748-4756.1998 snippet: The frameshift mutation completely abolished host resistance to phages p2 and c21 notes: Emond et al. localized the phage-resistance phenotype to the abiQ open reading frame on the pSRQ900 fragment. - reference: DOI:10.1128/JB.00296-13 snippet: Lactococcus lactis AbiQ system, a type III toxin-antitoxin with antiviral activities notes: Samson et al. support the type III protein-RNA toxin-antitoxin architecture of AbiQ. - reference: DOI:10.1128/JB.00296-13 snippet: AbiQ modified the early-expressed phage mRNA profiles notes: Samson et al. connect AbiQ to altered early phage mRNA profiles during infection. - reference: DOI:10.1128/JB.00296-13 snippet: active against various phage families infecting Gram-positive and Gram-negative bacteria notes: Samson et al. support AbiQ as an antiphage system whose activity is not restricted to its native lactococcal host. - reference: DOI:10.1128/JB.00296-13 snippet: In the presence of AbiQ, additional small transcripts were observed notes: Samson et al. observed altered P008 transcript profiles in phage-infected AbiQ-containing cells. canonical_examples: - taxon_id: NCBITaxon:1358 taxon_label: Lactococcus lactis note: Emond et al. isolated the pSRQ900 plasmid from Lactococcus lactis W-37, named its encoded abortive-infection mechanism AbiQ, and showed AbiQ-dependent resistance to c2- and 936-like lactococcal phages. reference: DOI:10.1128/AEM.64.12.4748-4756.1998 causal_graphs: - graph_id: abiq_type_iii_ta_antiphage_activity title: AbiQ type III toxin-antitoxin activity disrupts phage mRNA profiles description: Evidence-backed process sketch linking an AbiQ locus to type III toxin-antitoxin activity, altered early phage mRNA profiles, restricted phage propagation, and abortive-infection system possession. scope_status: NONMECHANISTIC scope_notes: The graph captures AbiQ at the system level without asserting a universal phage activator, exact AbiQ RNA target, or phage-escape path; Samson et al. show that multiple unrelated phage genes can be involved in the AbiQ phenotype. nodes: - node_id: abiq_locus label: AbiQ locus node_type: GENETIC_ELEMENT description: A type III toxin-antitoxin abortive-infection locus encoding the AbiQ toxin with its cognate RNA antitoxin. - node_id: abiq_type_iii_toxin_antitoxin_activity label: AbiQ type III toxin-antitoxin activity node_type: BIOLOGICAL_PROCESS description: Protein-RNA toxin-antitoxin activity of AbiQ, in which the AbiQ protein acts as an endoribonuclease neutralized by a cognate RNA antitoxin. - node_id: early_phage_mrna_profile_modification label: early phage mRNA profile modification node_type: BIOLOGICAL_PROCESS description: AbiQ-associated alteration of early phage mRNA profiles in infected host cells. - node_id: restricted_phage_propagation label: restricted phage propagation node_type: BIOLOGICAL_PROCESS description: Reduced production of infectious phage from an AbiQ-containing infected host cell. - node_id: abiq_system_trait label: AbiQ system node_type: TRAIT grounding: traitmech:000225 description: Possession of a genome-encoded AbiQ type III toxin-antitoxin abortive-infection system. - node_id: abortive_infection_system_trait label: abortive infection system node_type: TRAIT grounding: traitmech:000214 description: Possession of a genome-encoded abortive-infection phage defense system. edges: - subject: abiq_locus predicate: contributes to predicate_id: RO:0002326 object: abiq_type_iii_toxin_antitoxin_activity description: The AbiQ locus encodes a type III protein-RNA toxin-antitoxin antiphage system. evidence: - reference: DOI:10.1128/JB.00296-13 snippet: Lactococcus lactis AbiQ system, a type III toxin-antitoxin with antiviral activities notes: Samson et al. define AbiQ as a type III toxin-antitoxin system with antiviral activity. - subject: abiq_type_iii_toxin_antitoxin_activity predicate: contributes to predicate_id: RO:0002326 object: early_phage_mrna_profile_modification description: AbiQ activity alters the abundance pattern of early-expressed phage transcripts during infection. evidence: - reference: DOI:10.1128/JB.00296-13 snippet: AbiQ modified the early-expressed phage mRNA profiles notes: Samson et al. directly assayed phage transcription in AbiQ-containing Lactococcus cells. - subject: abiq_type_iii_toxin_antitoxin_activity predicate: contributes to predicate_id: RO:0002326 object: restricted_phage_propagation description: AbiQ type III toxin-antitoxin activity contributes to restricted phage propagation in infected host cells. evidence: - reference: DOI:10.1128/JB.00296-13 snippet: active against various phage families infecting Gram-positive and Gram-negative bacteria notes: Samson et al. support AbiQ as an antiphage type III toxin-antitoxin system. - subject: restricted_phage_propagation predicate: confers predicate_id: METPO:2007700 object: abiq_system_trait description: Restriction of phage propagation realizes the AbiQ antiphage defense trait. evidence: - reference: DOI:10.1128/AEM.64.12.4748-4756.1998 snippet: The frameshift mutation completely abolished host resistance to phages p2 and c21 notes: Emond et al. measured reduced phage plaquing on cells carrying the native AbiQ plasmid. - subject: abiq_system_trait predicate: is a predicate_id: rdfs:subClassOf object: abortive_infection_system_trait description: AbiQ system possession is an abortive-infection-system trait. evidence: - reference: DOI:10.1128/AEM.64.12.4748-4756.1998 snippet: the system encoded by pSRQ900 was classified as an abortive infection mechanism and was named AbiQ notes: Emond et al. place AbiQ in the abortive infection class of phage defense. curation_history: - timestamp: '2026-09-15T18:45:00Z' curator: codex action: MINTED_TRAITMECH_ID changes: Minted AbiQ system as a DOI-backed GENOMICS TraitRecord under the abortive infection system parent 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_v102. llm_assisted: true