Rip1: a prophage-encoded pore-forming protein that senses phage portal and terminase rings to defend bacteria (Nature)

Patel and colleagues describe in Nature a 164-residue prophage-encoded defence protein, ring interacting pore 1 (Rip1), that is activated by the portal or small terminase proteins of infecting phages, oligomeric ring-shaped complexes essential for virion maturation. Rip1 uses these rings as a template to assemble into membrane-disrupting pores that inhibit phage virion assembly and cause premature death of the host cell; homologues are widely distributed across bacteria and defend against diverse phages.