ApsAB system

traitmech:000328 · CLASS · PROPOSED

A genomics trait describing possession of an ApsAB anti-plasmid defense locus encoding the nuclease/helicase ApsA and Argonaute-like ApsB proteins that can destabilize high- and low-copy-number plasmids.

Trait evidence (5)

DOI:10.1038/s41467-024-48219-y
a novel antiplasmid system ApsAB actively involved in pOXA-48 destabilization

Zongo et al. support ApsAB as a named anti-plasmid system involved in pOXA-48 destabilization.
DOI:10.1038/s41467-024-48219-y
We show that ApsAB targets high and low-copy number plasmids.

Zongo et al. support anti-plasmid activity against both high- and low-copy-number plasmids.
DOI:10.1038/s41467-024-48219-y
ApsAB combines a nuclease/helicase protein and a novel type of Argonaute-like protein.

Zongo et al. support a two-component ApsAB system combining ApsA nuclease/helicase and Argonaute-like ApsB proteins.
DOI:10.1038/s41467-024-48219-y
This confirmed that F3141-F3140 corresponds to a novel antiplasmid defense system that we renamed apsAB for antiplasmid system AB.

Zongo et al. support apsAB as the expanded name for the F3141-F3140 anti-plasmid defense locus.
https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/List_system_article.md
ApsAB | 10\.1038/s41467-024-48219-y | An antiplasmid system drives antibiotic resistance gene integration in carbapenemase-producing Escherichia coli lineages

The DefenseFinder article registry maps the named ApsAB system to the Zongo et al. Escherichia coli anti-plasmid-system paper; the pinned DefenseFinder HMM inventory and rules table do not list ApsAB, so this row is name-to-paper evidence rather than model-component evidence.

ApsAB loci destabilize plasmids

Conservative system-level sketch linking possession of an ApsAB locus to plasmid destabilization without asserting the unresolved guide source, recognition rule, or degradation chemistry.

NONMECHANISTIC · The graph captures ApsAB as a named anti-plasmid defense system while leaving the direct ApsB guide source, the target-recognition rule, the exact plasmid-degradation chemistry, the natural plasmid substrate range, family breadth, and the absence of pinned DefenseFinder HMM or rule rows unresolved.

Edge evidence

ApsAB locus contributes to plasmid destabilization RO:0002326
The F3141-F3140 locus was renamed apsAB and ApsAB expression promotes plasmid elimination.
- DOI:10.1038/s41467-024-48219-y This confirmed that F3141-F3140 corresponds to a novel antiplasmid defense system that we renamed apsAB for antiplasmid system AB. Zongo et al. identify F3141-F3140 as the ApsAB anti-plasmid system.
- DOI:10.1038/s41467-024-48219-y These results indicate that ApsAB actively eliminates the plasmid, likely by promoting its degradation Zongo et al. report active ApsAB-mediated plasmid elimination after arabinose induction.
- DOI:10.1038/s41467-024-48219-y Both systems were found to destabilize a ColE1 multicopy plasmid Zongo et al. found that homologous E. coli ApsAB-like systems can destabilize a ColE1 multicopy plasmid.
plasmid destabilization confers ApsAB system METPO:2007700
ApsAB-mediated plasmid destabilization realizes the ApsAB system trait.
- DOI:10.1038/s41467-024-48219-y We show that ApsAB targets high and low-copy number plasmids. Zongo et al. support the ApsAB anti-plasmid output against high- and low-copy-number plasmids.
- https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/List_system_article.md ApsAB | 10\.1038/s41467-024-48219-y | An antiplasmid system drives antibiotic resistance gene integration in carbapenemase-producing Escherichia coli lineages The DefenseFinder article registry maps the named ApsAB system to the Zongo et al. Escherichia coli anti-plasmid-system paper; the pinned DefenseFinder HMM inventory and rules table do not list ApsAB, so this row is name-to-paper evidence rather than model-component evidence.

Provenance

Identifier source: TraitMech local identifier
Definition source: DOI:10.1038/s41467-024-48219-y

Parent traits (1)

quality METPO:1000188

Synonyms (2)

ApsAB EXACT_SYNONYM · DOI:10.1038/s41467-024-48219-y
apsAB EXACT_SYNONYM · DOI:10.1038/s41467-024-48219-y

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.

Escherichia coli NCBITaxon:562 DOI:10.1038/s41467-024-48219-y Zongo et al. identified ApsAB in ST38 Escherichia coli and found that homologous E. coli ApsAB-like systems also destabilized a ColE1 multicopy plasmid.

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 ApsAB guide sources, plasmid substrates, and model coverage before minting narrower ApsAB mechanism children.

KNOWLEDGE GAP OPEN apsab-substrate-and-guide-source-gap · raised by codex · 2026-09-21

Attached to causal_graphs#apsab_locus_destabilizes_plasmids

Zongo et al. support ApsAB as a two-component E. coli anti-plasmid system and report activity against high- and low-copy-number plasmids, but the direct ApsB guide source, the target-recognition rule, exact plasmid-degradation chemistry, natural substrate range, family-level breadth, and profile-to-component model are not resolved enough here to assert narrower mechanistic or subtype traits.

Curation history

2026-09-21T05:45:03Z · MINTED_TRAITMECH_ID · codex
Minted ApsAB system as a DOI-backed GENOMICS TraitRecord under the quality root after an ignored-and-hidden duplicate review found no exact live TraitMech, METPO, history, or prior proposal record; the replacement placeholder is reserved in proposals/metpo_traitmech_v205.