Fig. 5: Model for Tab-mediated defence and anti-Tab-mediated counter-defence.
From: Anti-phage defence through inhibition of virion assembly
During lysogeny (top), Tab is constitutively expressed from the JBD26 prophage; it detects the tape measure protein (TMP) of invading phages (purple). While DNA-filled heads and phage tail proteins are produced, tail assembly is blocked, and no mature phage particles are released. However, late-stage infection proceeds normally, leading to the accumulation of phage lysis proteins that eventually kill the cell. Since phages are not produced, secondary infections do not occur, and the bacterial community is protected. When the JBD26 prophage switches to the lytic cycle (bottom), anti-Tab is produced and binds to and sequesters Tab, allowing JBD26 replication to proceed normally. ST small terminase, LT large terminase. Created with BioRender.com.
