FS_HP
Description
PICIs (Phage-inducible chromosomal islands) are highly mobile genetic elements that reside in the bacterial chromosome in the absence of a helper phage. Following infection by the helper phage, PICIs excise and replicate by hijacking the helper phage machinery. The FS_HP system was discovered in *E. fergusonii through the manual search for immune systems in flanking regions of gram-negative PICIs (N/A) . It is composed of a single protein with a hypothetical domain, from which it derives the HP part of its name. The system showcases a broad defense spectrum. It was tested against 15 lytic phages in 3 gram-negative bacteria and protected the bacterial host against 3 unrelated phages in 2 different bacteria species. FS_HP also blocked the formation of phage particles upon induction of the P22 S. enterica prophage. Therefore, the system can block phage in both lytic and lysogenic life cycles. It was also shown to reduce the production of transducing particles.
Molecular mechanisms
As far as we are aware, the molecular mechanism is unknown.
Example of genomic structure
The FS_HP is composed of 1 protein: HP.
Here is an example found in the RefSeq database:
The FS_HP system in Escherichia coli (GCF_016944735.1, NZ_CP063511) is composed of 1 protein: HP (WP_227456581.1)
Distribution of the system among prokaryotes
Structure
Group | Structure | Foldseek | System | Gene name | Subtype | Proteins in structure | System genes | Prediction type | N genes in sys | pLDDT | iptm+ptm | pDockQ |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| No data available | ||||||||||||