Fig. 7: Proposed model for Zorya anti-phage mechanism.
From: Modularity of Zorya defense systems during phage inhibition
(i) Inactive Zorya systems are embedded within the bacterial inner membrane. (ii) Upon infection, phage-mediated puncturing pushes down the peptidoglycan (PG) layer or causes PG damage, an event that can be ‘sensed’ by the ZorB PG-binding domain. This triggers a conformational change in ZorAB, opening the ion channel and leading to the rotation of ZorA rod-like extensions within the cytoplasm. ZorA-rod will recruit a nuclease complex to prevent phage infection by predominantly targeting bacterial chromosomes. In the case of Zorya II, ZorAB II-mediated recruitments increase the local concentration of ZorE, enabling full efficiency of its nicking activity. Created in BioRender. Mariano, G. (2025) https://BioRender.com/w85a533.
