diff --git a/content/3.defense-systems/pfiat.md b/content/3.defense-systems/pfiat.md index 4f3afebf045e64b0d1100aa0fd448bf94f328c52..4253daa2ec1f718de040db6cff99937486d69a10 100644 --- a/content/3.defense-systems/pfiat.md +++ b/content/3.defense-systems/pfiat.md @@ -10,25 +10,50 @@ tableColumns: Activator: Unknown Effector: Unknown PFAM: PF02604, PF05016 +contributors: + - Helena Shomar + - Marie Guillaume + - Florian Tesson relevantAbstracts: - - doi: 10.1111/1751-7915.13570 + - doi: 10.1111/1751-7915.13570 --- # PfiAT + +## Description + +PfiAT is a toxin-antitoxin system discovered in 2020 :ref{doi=10.1111/1751-7915.13570}. + +The role of PfiAT as an antiphage system is not certain and might be removed from DefenseFinder. This system is known to inhibit the Pf4 prophage from *Pseudomonas aeruginosa*. + +The PfiAT system is composed of two small proteins: the antitoxin PfiA and the toxin PfiT. + +## Molecular mechanism + +The PfiAT system acts as a regulator of the Pf4 prophages :ref{doi=10.1111/1751-7915.13570}. The PfiAT complex will autorepress its own locus. + +In the absence of PfiT, PfiA is not able to bind to the promotor. This change leads to the expression of xisF4 and PA0727 leading to the phage replication and excretion. + + ## Example of genomic structure +The PfiAT is composed of 2 proteins: PfiA and PfiT. The PfiAT is composed of 2 proteins: PfiA and PfiT. +Here is an example found in the RefSeq database: Here is an example found in the RefSeq database: {max-width=750px} +The PfiAT system in *Desulfoscipio gibsoniae* (GCF_000233715.2, NC_021184) is composed of 2 proteins PfiA (WP_006521270.1) PfiT (WP_006521271.1) The PfiAT system in *Desulfoscipio gibsoniae* (GCF_000233715.2, NC_021184) is composed of 2 proteins PfiA (WP_006521270.1) PfiT (WP_006521271.1) ## Distribution of the system among prokaryotes +Among the 22,803 complete genomes of RefSeq, the PfiAT is detected in 819 genomes (3.59 %). Among the 22,803 complete genomes of RefSeq, the PfiAT is detected in 819 genomes (3.59 %). +The system was detected in 308 different species. The system was detected in 308 different species. {max-width=750px} @@ -36,10 +61,14 @@ The system was detected in 308 different species. Proportion of genome encoding the PfiAT system for the 14 phyla with more than 50 genomes in the RefSeq database. +Proportion of genome encoding the PfiAT system for the 14 phyla with more than 50 genomes in the RefSeq database. + + ## Structure ### PfiAT ##### Example 1 +##### Example 1 ::molstar-pdbe-plugin --- @@ -47,6 +76,15 @@ height: 700 dataUrls: - /pfiat/PfiAT.PfiAT__PfiA.0.V.cif - /pfiat/PfiAT.PfiAT__PfiT.0.V.cif +dataUrls: + - /pfiat/PfiAT.PfiAT__PfiA.0.V.cif + - /pfiat/PfiAT.PfiAT__PfiT.0.V.cif --- :: + +## Experimental validation + +To our knowledge, no experimental validation of this toxin-antitoxin system exists. +It was shown to regulate the replication and expression of the prophage Pf4. +