PsyrTA

Contributors: Ernest Mordret

Description

Originally found in a high throughput shotgun cloning of bacterial fragments in E. coli looking for Toxin-Antitoxin pairs. PsyrTA is composed of two proteins, PsyrT, the toxin, is a RecQ family DNA helicase, and PsyrA, the antitoxin, was shown to be a Nucleotide-binding protein. Note that that system is sometimes called RqlHI () , where RqlH refers to PsyrT and RqlI to PsyrA.

Molecular mechanisms

from () :

The psyrT shares homology with domains of the RecQ helicase, a family of proteins implicated in DNA repair (Bernstein et al., 2010); and the antitoxin of the same system, psyrA, has a nucle- otide binding domain (COG0758) that was previously described in proteins involved in DNA uptake

from () :

Both systems encode an antitoxin with homology to DprA, a single-stranded DNA (ssDNA)-binding protein known to be involved in DNA transformation (Mortier- Barrière et al., 2007). The toxin contains a phosphoribosyl trans- ferase (PRTase) domain, which was previously found in effectors of retron abortive infection systems "

Example of genomic structure

The PsyrTA is composed of 2 proteins: PsyrA and PsyrT.

Here is an example found in the RefSeq database:

The PsyrTA system in Providencia rettgeri (GCF_013702265.1, NZ_CP059348) is composed of 2 proteins PsyrT (WP_049246657.1) PsyrA (WP_001103168.1)

Distribution of the system among prokaryotes

Among the 22,803 complete genomes of RefSeq, the PsyrTA is detected in 629 genomes (2.76 %).

The system was detected in 132 different species.

Proportion of genome encoding the PsyrTA system for the 14 phyla with more than 50 genomes in the RefSeq database.

Structure

PsyrTA

Example 1

Experimental validation

      
graph LR;
    Millman_2022[Millman et al., 2022] --> Origin_0
    Origin_0[Bacillus sp. FJAT-29814 
2746452868, 2746452867] --> Expressed_0[Escherichia coli]
    Expressed_0[Escherichia coli] ----> T2 & T4 & T6
    subgraph Title1[Reference]
        Millman_2022
end
    subgraph Title2[System origin]
        Origin_0
end
    subgraph Title3[Expression species]
        Expressed_0
end
    subgraph Title4[Protects against]
        T2
        T4
        T6
end
    style Title1 fill:none,stroke:none,stroke-width:none
    style Title2 fill:none,stroke:none,stroke-width:none
    style Title3 fill:none,stroke:none,stroke-width:none
    style Title4 fill:none,stroke:none,stroke-width:none

    
::

References

10.1016/j.chom.2022.09.017
no authors
no containerTitle ()
10.1016/j.molcel.2013.02.002
no authors
no containerTitle ()
10.1371/journal.ppat.1005317
no authors
no containerTitle ()