PD-T7-3 system

traitmech:000405 · CLASS · PROPOSED

A phage defense system in which an organism possesses a PD-T7-3 locus represented by DefenseFinder as a single-profile model, PD-T7-3__PD-T7-3, and experimentally linked to protection against T2, T4, T6, T5, SECphi17, T3, and T7 when expressed in E. coli.

Trait evidence (9)

DOI:10.1038/s41564-022-01219-4
Here we developed an experimental selection scheme agnostic to genomic context to identify defence systems in 71 diverse E. coli strains. Our results unveil 21 conserved defence systems, none of which were previously detected as enriched in defence islands.

Vassallo et al. developed the agnostic E. coli pangenome selection that uncovered PD-T7-3 and related conserved phage-defense systems.
https://gitlab.pasteur.fr/mdm-lab/wiki/-/raw/ee7647d8/content/3.defense-systems/pd-t7-3.md
PD-T7-3 systems were discovered to be anti-phage systems during an experimental screen performed on *E. coli* strains :ref{doi=10.1038/s41564-022-01219-4}

The DefenseFinder wiki describes PD-T7-3 as a phage-defense system discovered in an E. coli experimental screen.
https://gitlab.pasteur.fr/mdm-lab/wiki/-/raw/ee7647d8/content/3.defense-systems/pd-t7-3.md
As far as we are aware, the molecular mechanism of PD-T7-3 is unknown.

The DefenseFinder wiki records the PD-T7-3 molecular mechanism as unresolved.
https://gitlab.pasteur.fr/mdm-lab/wiki/-/raw/ee7647d8/content/3.defense-systems/pd-t7-3.md
The PD-T7-3 is composed of 1 protein: PD-T7-3.

The DefenseFinder wiki names PD-T7-3 as a single-protein system.
https://gitlab.pasteur.fr/mdm-lab/wiki/-/raw/ee7647d8/content/3.defense-systems/pd-t7-3.md
The PD-T7-3 system in *Paraglaciecola psychrophila* (GCF_000347635.1, NC_020514) is composed of 1 protein: PD-T7-3 (WP_007636449.1)

The DefenseFinder wiki illustrates a predicted one-protein PD-T7-3 locus in RefSeq assembly GCF_000347635.1 on NC_020514.
https://gitlab.pasteur.fr/mdm-lab/wiki/-/raw/ee7647d8/content/3.defense-systems/pd-t7-3.md
Vassallo_2022[<a href='https://doi.org/10.1038/s41564-022-01219-4'>Vassallo et al., 2022</a>] --> Origin_0 Origin_0[Escherichia coli <a href='https://ncbi.nlm.nih.gov/protein/RCP48690.1'>RCP48690.1</a>] --> Expressed_0[Escherichia coli] Expressed_0[Escherichia coli] ----> T2 & T4 & T6 & T5 & SECphi17 & T3 & T7

The DefenseFinder experimental-validation diagram links Vassallo et al. to an E. coli PD-T7-3 source locus expressed in E. coli against T2, T4, T6, T5, SECphi17, T3, and T7.
https://gitlab.pasteur.fr/mdm-lab/wiki/-/raw/ee7647d8/content/3.defense-systems/pd-t7-3.md
subgraph Title4[Protects against] T2 T4 T6 T5 SECphi17 T3 T7

The DefenseFinder experimental-validation diagram lists T2, T4, T6, T5, SECphi17, T3, and T7 in the PD-T7-3 protects-against subgraph.
https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/DefenseFinder_rules.tsv
PD-T7-3 PD-T7-3 1 1 PD-T7-3__PD-T7-3

The DefenseFinder rules table models PD-T7-3 as a single-profile system requiring PD-T7-3__PD-T7-3.
https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/Liste_hmm_system.md
| PD-T7-3__PD-T7-3 | PD-T7-3__PD-T7-3 | PD-T7-3 | Custom | 100 |

The DefenseFinder HMM inventory records PD-T7-3__PD-T7-3 under the PD-T7-3 system namespace.

PD-T7-3 loci restrict T2, T4, T6, T5, SECphi17, T3, and T7

Conservative system-level sketch linking possession of a PD-T7-3 locus to protection against T2, T4, T6, T5, SECphi17, T3, and T7.

NONMECHANISTIC · The graph captures PD-T7-3 as a named DefenseFinder phage-defense system while leaving natural host breadth, the direct phage trigger, and the effector mechanism unresolved.

Edge evidence

PD-T7-3 locus contributes to T2, T4, T6, T5, SECphi17, T3, and T7 protection RO:0002326
The DefenseFinder wiki links a PD-T7-3 locus from Vassallo et al. to protection against T2, T4, T6, T5, SECphi17, T3, and T7, and DefenseFinder models PD-T7-3 through one mandatory profile.
- https://gitlab.pasteur.fr/mdm-lab/wiki/-/raw/ee7647d8/content/3.defense-systems/pd-t7-3.md PD-T7-3 systems were discovered to be anti-phage systems during an experimental screen performed on *E. coli* strains :ref{doi=10.1038/s41564-022-01219-4} The DefenseFinder wiki describes PD-T7-3 as a phage-defense system discovered in an E. coli experimental screen.
- https://gitlab.pasteur.fr/mdm-lab/wiki/-/raw/ee7647d8/content/3.defense-systems/pd-t7-3.md As far as we are aware, the molecular mechanism of PD-T7-3 is unknown. The DefenseFinder wiki records the PD-T7-3 molecular mechanism as unresolved.
- https://gitlab.pasteur.fr/mdm-lab/wiki/-/raw/ee7647d8/content/3.defense-systems/pd-t7-3.md The PD-T7-3 is composed of 1 protein: PD-T7-3. The DefenseFinder wiki names PD-T7-3 as a single-protein system.
- https://gitlab.pasteur.fr/mdm-lab/wiki/-/raw/ee7647d8/content/3.defense-systems/pd-t7-3.md Vassallo_2022[<a href='https://doi.org/10.1038/s41564-022-01219-4'>Vassallo et al., 2022</a>] --> Origin_0 Origin_0[Escherichia coli <a href='https://ncbi.nlm.nih.gov/protein/RCP48690.1'>RCP48690.1</a>] --> Expressed_0[Escherichia coli] Expressed_0[Escherichia coli] ----> T2 & T4 & T6 & T5 & SECphi17 & T3 & T7 The DefenseFinder experimental-validation diagram links Vassallo et al. to an E. coli PD-T7-3 source locus expressed in E. coli against T2, T4, T6, T5, SECphi17, T3, and T7.
- https://gitlab.pasteur.fr/mdm-lab/wiki/-/raw/ee7647d8/content/3.defense-systems/pd-t7-3.md subgraph Title4[Protects against] T2 T4 T6 T5 SECphi17 T3 T7 The DefenseFinder experimental-validation diagram lists T2, T4, T6, T5, SECphi17, T3, and T7 in the PD-T7-3 protects-against subgraph.
- https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/DefenseFinder_rules.tsv PD-T7-3 PD-T7-3 1 1 PD-T7-3__PD-T7-3 The DefenseFinder rules table models PD-T7-3 as a single-profile system requiring PD-T7-3__PD-T7-3.
- https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/Liste_hmm_system.md | PD-T7-3__PD-T7-3 | PD-T7-3__PD-T7-3 | PD-T7-3 | Custom | 100 | The DefenseFinder HMM inventory records PD-T7-3__PD-T7-3 under the PD-T7-3 system namespace.
T2, T4, T6, T5, SECphi17, T3, and T7 protection confers PD-T7-3 system METPO:2007700
Protection against T2, T4, T6, T5, SECphi17, T3, and T7 realizes the PD-T7-3 system trait.
- https://gitlab.pasteur.fr/mdm-lab/wiki/-/raw/ee7647d8/content/3.defense-systems/pd-t7-3.md Vassallo_2022[<a href='https://doi.org/10.1038/s41564-022-01219-4'>Vassallo et al., 2022</a>] --> Origin_0 Origin_0[Escherichia coli <a href='https://ncbi.nlm.nih.gov/protein/RCP48690.1'>RCP48690.1</a>] --> Expressed_0[Escherichia coli] Expressed_0[Escherichia coli] ----> T2 & T4 & T6 & T5 & SECphi17 & T3 & T7 The DefenseFinder experimental-validation diagram links Vassallo et al. to an E. coli PD-T7-3 source locus expressed in E. coli against T2, T4, T6, T5, SECphi17, T3, and T7.
- https://gitlab.pasteur.fr/mdm-lab/wiki/-/raw/ee7647d8/content/3.defense-systems/pd-t7-3.md subgraph Title4[Protects against] T2 T4 T6 T5 SECphi17 T3 T7 The DefenseFinder experimental-validation diagram lists T2, T4, T6, T5, SECphi17, T3, and T7 in the PD-T7-3 protects-against subgraph.
PD-T7-3 system is a phage defense system rdfs:subClassOf
PD-T7-3 system possession is a phage-defense-system trait.
- DOI:10.1038/s41564-022-01219-4 Here we developed an experimental selection scheme agnostic to genomic context to identify defence systems in 71 diverse E. coli strains. Our results unveil 21 conserved defence systems, none of which were previously detected as enriched in defence islands. Vassallo et al. developed the agnostic E. coli pangenome selection that uncovered PD-T7-3 and related conserved phage-defense systems.
- https://gitlab.pasteur.fr/mdm-lab/wiki/-/raw/ee7647d8/content/3.defense-systems/pd-t7-3.md The PD-T7-3 is composed of 1 protein: PD-T7-3. The DefenseFinder wiki names PD-T7-3 as a single-protein system.
- https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/DefenseFinder_rules.tsv PD-T7-3 PD-T7-3 1 1 PD-T7-3__PD-T7-3 The DefenseFinder rules table models PD-T7-3 as a single-profile system requiring PD-T7-3__PD-T7-3.

Provenance

Identifier source: TraitMech local identifier
Definition source: https://gitlab.pasteur.fr/mdm-lab/wiki/-/raw/ee7647d8/content/3.defense-systems/pd-t7-3.md

Parent traits (1)

phage defense system traitmech:000209

Synonyms (2)

PD-T7-3 RELATED_SYNONYM · https://gitlab.pasteur.fr/mdm-lab/wiki/-/raw/ee7647d8/content/3.defense-systems/pd-t7-3.md
PD-T7-3__PD-T7-3 RELATED_SYNONYM · https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/Liste_hmm_system.md

kg-microbe context

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

Discussions and Knowledge Gaps (2)

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

Resolve PD-T7-3 natural host breadth, direct phage trigger, and effector mechanism before minting narrower PD-T7-3 mechanism traits.

KNOWLEDGE GAP OPEN pd-t7-3-mechanism-gap · raised by codex · 2026-09-27

Attached to causal_graphs#pd_t7_3_locus_restricts_phages

Vassallo et al. support PD-T7-3 as one of the conserved systems from an E. coli pangenome phage-defense selection, the DefenseFinder wiki maps the source locus to protection against T2, T4, T6, T5, SECphi17, T3, and T7, and DefenseFinder represents the system with one profile. Natural host breadth, the direct phage trigger, and effector logic remain unresolved.

Evidence

DOI:10.1038/s41564-022-01219-4
Here we developed an experimental selection scheme agnostic to genomic context to identify defence systems in 71 diverse E. coli strains. Our results unveil 21 conserved defence systems, none of which were previously detected as enriched in defence islands.
https://gitlab.pasteur.fr/mdm-lab/wiki/-/raw/ee7647d8/content/3.defense-systems/pd-t7-3.md
PD-T7-3 systems were discovered to be anti-phage systems during an experimental screen performed on *E. coli* strains :ref{doi=10.1038/s41564-022-01219-4}
https://gitlab.pasteur.fr/mdm-lab/wiki/-/raw/ee7647d8/content/3.defense-systems/pd-t7-3.md
As far as we are aware, the molecular mechanism of PD-T7-3 is unknown.
https://gitlab.pasteur.fr/mdm-lab/wiki/-/raw/ee7647d8/content/3.defense-systems/pd-t7-3.md
Vassallo_2022[<a href='https://doi.org/10.1038/s41564-022-01219-4'>Vassallo et al., 2022</a>] --> Origin_0 Origin_0[Escherichia coli <a href='https://ncbi.nlm.nih.gov/protein/RCP48690.1'>RCP48690.1</a>] --> Expressed_0[Escherichia coli] Expressed_0[Escherichia coli] ----> T2 & T4 & T6 & T5 & SECphi17 & T3 & T7
https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/DefenseFinder_rules.tsv
PD-T7-3 PD-T7-3 1 1 PD-T7-3__PD-T7-3
https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/Liste_hmm_system.md
| PD-T7-3__PD-T7-3 | PD-T7-3__PD-T7-3 | PD-T7-3 | Custom | 100 |

Recheck whether DefenseFinder adds a PD-T7-3 List_system_article.md row before using the article registry as direct PD-T7-3 model-to-paper evidence.

CURATION TODO OPEN pd-t7-3-defensefinder-article-registry-gap · raised by codex · 2026-09-27

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.

The pinned DefenseFinder wiki, rules table, and HMM inventory all represent PD-T7-3, but the pinned List_system_article.md registry omits a PD-T7-3 row. The PD-T7-3 record therefore cites the pinned wiki plus the DOI-backed Vassallo et al. screen instead of inventing a missing article-registry entry.

Evidence

https://gitlab.pasteur.fr/mdm-lab/wiki/-/raw/ee7647d8/content/3.defense-systems/pd-t7-3.md
PD-T7-3 systems were discovered to be anti-phage systems during an experimental screen performed on *E. coli* strains :ref{doi=10.1038/s41564-022-01219-4}
https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/DefenseFinder_rules.tsv
PD-T7-3 PD-T7-3 1 1 PD-T7-3__PD-T7-3
https://raw.githubusercontent.com/mdmparis/defense-finder-models/afb0e5a8b466be53586b13266f5d38d98c3ac268/Liste_hmm_system.md
| PD-T7-3__PD-T7-3 | PD-T7-3__PD-T7-3 | PD-T7-3 | Custom | 100 |

Curation history

2026-09-27T08:02:09Z · MINTED_TRAITMECH_ID · codex
Minted PD-T7-3 system as a DOI- and DefenseFinder-backed GENOMICS TraitRecord under phage defense system 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_v282.
2026-09-27T08:02:10Z · REVIEW_CANONICAL_EXAMPLE_EVIDENCE_GAP · codex
Reviewed PD-T7-3 system canonical_examples and left them empty because the current sources support an E. coli accession-level experimental validation graph, a DefenseFinder system model, and a RefSeq Paraglaciecola psychrophila example, but not a direct native microbial isolate exemplar with experimentally verified endogenous PD-T7-3 activity. No paid research was used.