This family of holins is found in several staphylococcal and streptococcal bacteriophages. Holins are a diverse family of proteins that cause bacterial membrane lysis during late-protein synthesis. It is thought that the temporal precision of holin-mediated lysis may occur through the buildup of a holin oligomer which causes the lysis.
Jiyao W et al.(2023). "The conserved domain database in 2023.",