This entry (previously known as DUF262) represents a domain found N-terminal in the GmrSD family of modification-dependent restriction endonuclease, including BrxU and SspE proteins [1,2]. BrxU is a type IV DNA modification-dependent restriction enzy ...
This entry (previously known as DUF262) represents a domain found N-terminal in the GmrSD family of modification-dependent restriction endonuclease, including BrxU and SspE proteins [1,2]. BrxU is a type IV DNA modification-dependent restriction enzyme, which is promiscuous and uses a range of nucleotide and metal co-factors to recognise and cleave DNA that contains any of at least three different modifications, and this activity is dependent on the initial nucleotide-driven dissociation of BrxU dimers, and subsequent nucleotide hydrolysis [1]. SspE is a dual-function protein that exerts both N-terminal NTPase and C-terminal DNA nicking nuclease activities to defend against phage infection [2]. BrxU targets and cleaves DNA containing one of at least three DNA modifications, 5mC, 5hmC or glc-5hmC whereas 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 is involved in nucleotide binding, recognition and hydrolysis.