RT-nitrilase-Tm

Description

RT-nitrilase-Tm (also named UG5-large) is a two-gene defense system. It was discovered from P4-like satellites in E. coli genomes (N/A) (N/A) . Its antiphage activity was shown in E. coli against phage AL505_P2 (Myoviridae).

The first protein is a reverse transcriptase (RT) fussed with C-N hydrolase domain (nitrilase); the second protein is transmembrane protein (N/A) .

The presence of an RT protein allows to draw a parallel between this system and DRT, AbiA, AbiK and AbiP2.

Molecular mechanism

As far as we are aware, the molecular mechanism is unknown.

Example of genomic structure

The Rst_RT-nitrilase-Tm is composed of 2 proteins: RT and RT-Tm.

Here is an example found in the RefSeq database:

The Rst_RT-Tm system in Morganella morganii (GCF_900478755.1, NZ_LS483498) is composed of 2 proteins RT (WP_061057569.1) RT-Tm (WP_004234654.1)

Distribution of the system among prokaryotes

Structure

Experimental validation

      
graph LR;
    Rousset_2022[Rousset et al., 2022] --> Origin_0
    Origin_0[Escherichia coli P4 loci  
WP_000628823.1, WP_000094232.1] --> Expressed_0[Escherichia coli]
    Expressed_0[Escherichia coli] ----> Al505_P2
    subgraph Title1[Reference]
        Rousset_2022
end
    subgraph Title2[System origin]
        Origin_0
end
    subgraph Title3[Expression species]
        Expressed_0
end
    subgraph Title4[Protects against]
        Al505_P2
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