Structural studies of prokaryotic immune systems

Bacteria and archaea have both innate and adaptive immune systems to defend against viral infection. Innate defences range from the identification and cleavage of the viral DNA by restriction nucleases to the suicidal death of infected host cells.

Adaptive immunity, on the other hand, involves the creation of an immune memory that targets specific phages in case of reinfection. Structural biology played a fundamental role in understanding the molecular mechanisms of such systems, shedding light on their functions as well as enabling their use in biotechnology.

Here, I will present recent work from my laboratory, showing how cryo-EM enabled us to visualise prokaryotic immune systems in action.