Overview

• Researchers published the cryo-EM structure of Kiwa in Cell, revealing how its subunits KwaA and KwaB assemble at phage attachment sites to block viral DNA injection
• KwaA senses phage binding at the membrane and activates KwaB to capture and inactivate injected viral DNA before it can replicate
• Some phages produce a DNA-mimic protein Gam to lure KwaB away from real targets; pairing Kiwa with the RecBCD system preserves defense integrity
• The team has cataloged over 600 environmental phages and is soliciting public water samples to identify viruses capable of overcoming bacterial firewalls
• Insights into Kiwa’s mechanism and phage counter-strategies aim to accelerate development of targeted therapies against antibiotic-resistant infections