TraitMech

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DISARM system

traitmech:000211 · CLASS · PROPOSED

A genomics trait describing possession of a Defense Island System Associated with Restriction-Modification locus that uses methyltransferase-associated self/non-self discrimination and DrmAB activation to inhibit bacteriophage DNA replication.

Trait evidence (4)

  • DOI:10.1038/s41564-017-0051-0
    Our results establish DISARM as a new defence system, providing protection against diverse phages

    Ofir et al. experimentally established DISARM as a phage defense system and distinguished its intracellular block from phage-adsorption phenotypes.

  • DOI:10.1038/s41564-017-0051-0
    The DISARM system is widespread in defence islands across the microbial world

    Ofir et al. support DISARM as a recurring microbial defense island system rather than a single source-specific locus.

  • DOI:10.1038/s41467-022-30673-1
    DISARM (Defense Island System Associated with Restriction-Modification) systems can provide protection against a wide range of phage

    Bravo et al. independently expand the DISARM acronym and frame DISARM as a broad anti-phage system.

  • DOI:10.1038/s41467-022-30673-1
    In vivo studies of structure-guided DrmAB mutants demonstrate that ATP hydrolysis, DNA binding, and DrmAB heterodimer formation are essential for phage targeting by DISARM

    Bravo et al. support the DrmAB activation mechanism recorded in the first causal graph.

DISARM senses phage DNA to activate DrmAB defense

Evidence-backed causal sketch linking DISARM methylation and 5-prime-overhang DNA sensing to DrmAB activation and blocked early phage DNA circularization.

MECHANISTIC · The graph captures host DNA methylation, 5-prime-overhang sensing, DrmAB activation, and early phage DNA restriction without asserting the unresolved downstream nuclease or replication-block coupling.

DISARM senses phage DNA to activate DrmAB defense Interactive directed graph showing evidence-backed causal relationships for DISARM system.

Edge evidence

  • DrmAB core complex contributes to DISARM DrmAB activation RO:0002326

    DrmA DNA binding, DrmA ATP hydrolysis, and DrmAB heterodimer formation are required for DISARM activation and phage targeting.

    • DOI:10.1038/s41467-022-30673-1 DNA binding, and DrmAB heterodimer formation are essential for phage targeting by DISARM Bravo et al. established the structural and functional importance of the DrmA-DrmB core complex.
  • DISARM host DNA methylation negatively regulates DISARM DrmAB activation RO:0002212

    DISARM host-DNA methylation limits DrmAB activation by self DNA.

    • DOI:10.1038/s41467-022-30673-1 methylated DNA limits the ATPase activity of DrmAB which is essential for anti-phage defense Bravo et al. support methylation-sensitive DrmAB activation as a self/non-self filter.
  • DISARM 5-prime-overhang DNA sensing activates DISARM DrmAB activation RO:0002213

    Unmethylated 5-prime-overhang DNA dislodges the DrmA trigger loop to activate DrmAB.

    • DOI:10.1038/s41467-022-30673-1 binding to DNA substrates containing a 5′ overhang dislodges the TL, initiating a long-range structural rearrangement for DrmAB activation Bravo et al. structurally support 5-prime-overhang-triggered DrmAB activation.
  • DISARM DrmAB activation mitigates phage DNA circularization METPO:2007407

    Activated DISARM blocks early phage DNA circularization and replication after phage entry.

    • DOI:10.1038/s41564-017-0051-0 phi3T was not able to circularize its genome or form detectible lysogens in DISARM-containing cells Ofir et al. showed that DISARM blocks an early intracellular step after phage adsorption.
  • DISARM DrmAB activation confers DISARM system METPO:2007700

    DrmAB activation realizes DISARM-mediated anti-phage defense.

    • DOI:10.1038/s41467-022-30673-1 provide the mechanism of targeting a wide range of phage by DISARM Bravo et al. linked DNA-interacting DrmA residues to DISARM anti-phage protection in vivo.
  • DISARM system is a phage defense system rdfs:subClassOf

    DISARM possession is a methyltransferase-associated phage-defense-system trait.

    • DOI:10.1038/s41564-017-0051-0 Our results establish DISARM as a new defence system Ofir et al. establish DISARM in the phage defense system family.

Protein and taxon examples

Graph nodeProteinTaxonUniProt statusRole and evidence
DrmAB core complex UniProtKB:P0DW05
DISARM protein DrmA (drmA) 		Bacillus paralicheniformis ATCC 9945a
NCBITaxon:766760 		REVIEWED
retrieved 2026-09-15 · entry v12 · sequence v1

B. paralicheniformis ATCC 9945a DrmA is the helicase-domain component of the class 2 DISARM DrmAB core.

  • DOI:10.1038/s41564-017-0051-0 Deletions of drmA (helicase domain), drmB (DUF1998 domain) and drmE (unknown function) abolished DISARM protection against all phages tested Ofir et al. tested scarless deletions in the native B. paralicheniformis ATCC 9945a DISARM locus; UniProt verifies the reviewed DrmA accession.
DrmAB core complex UniProtKB:P0DW06
DISARM protein DrmB (drmB) 		Bacillus paralicheniformis ATCC 9945a
NCBITaxon:766760 		REVIEWED
retrieved 2026-09-15 · entry v9 · sequence v1

B. paralicheniformis ATCC 9945a DrmB is the DUF1998 component paired with DrmA in the class 2 DISARM DrmAB core.

  • DOI:10.1038/s41564-017-0051-0 Deletions of drmA (helicase domain), drmB (DUF1998 domain) and drmE (unknown function) abolished DISARM protection against all phages tested Ofir et al. tested scarless deletions in the native B. paralicheniformis ATCC 9945a DISARM locus; UniProt verifies the reviewed DrmB accession.

Provenance

Identifier source
TraitMech local identifier
Definition source
DOI:10.1038/s41564-017-0051-0

Parent traits (1)

Children (2)

Synonyms (2)

  • Defense Island System Associated with Restriction-Modification EXACT_SYNONYM · DOI:10.1038/s41467-022-30673-1
  • Defense Island System Associated with Restriction Modification EXACT_SYNONYM · DOI:10.1038/s41467-022-30673-1

kg-microbe context

No kg-microbe node embedding matched this record in the 2026-04-25 deepwalk.

Canonical examples (1)

Organisms cited as exemplars of this trait. Taxon ids are NCBITaxon and link out to the NCBI record.

  • Bacillus paralicheniformis ATCC 9945a NCBITaxon:766760 DOI:10.1038/s41564-017-0051-0 Ofir et al. amplified the native B. paralicheniformis ATCC 9945a class 2 DISARM locus and integrated it into B. subtilis to test phage defense.

Discussions and Knowledge Gaps (1)

Open questions attached to this trait. Seeded by just knowledge-gap-scan and curated; see the corpus-wide index.

Resolve the downstream nuclease or replication-blocking effector coupled to activated DrmAB before adding a more specific DISARM phage-DNA degradation edge.

KNOWLEDGE GAP OPEN disarm-downstream-effector-gap · raised by codex · 2026-09-15

Not yet attached to a section of this record — a curator sets attaches_to (e.g. causal_graphs#some_edge) so the gap shows beside the mechanism it concerns.

Ofir et al. inferred phage DNA degradation and showed that DrmC is partially redundant across phages; Bravo et al. resolved DrmAB recognition and activation but left the downstream nuclease or physical replication block as a model.

Curation history

  1. · MINTED_TRAITMECH_ID · codex

    Minted DISARM system as a DOI-backed GENOMICS TraitRecord under the phage defense system parent with reviewed B. paralicheniformis ATCC 9945a DrmA and DrmB protein examples 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_v88.