The Linocin_M18 is found in eubacteria and archaea. These proteins, referred to as encapsulins, form nanocompartments within the bacterium which contain ferritin-like proteins or peroxidases, enzymes involved in oxidative-stress response. These enzymes are targeted to the interior of encapsulins via unique C-terminal extensions.
Jiyao W et al.(2023). "The conserved domain database in 2023.",