GmrSD restriction endonucleases, C-terminal domain
This entry (previously known as DUF1524) represents a domain found C-terminal in the GmrSD family of modification-dependent restriction endonucleases including SspE proteins. SspE is a dual-function protein that exerts both N-terminal NTPase and C-terminal DNA nicking nuclease activities to defend against phage infection. SspE has a phosphorothioate (PT) modification-binding preference and utilizes epigenetic PT modification to accomplish self-nonself discrimination and to coordinate its NTPase and DNA nicking activities to fight against phages. The domain represented in this entry has a DNA nicking nuclease activity and belongs to HNH nuclease superfamily.
Jiyao W et al.(2023). "The conserved domain database in 2023.",