Intracellular non-membrane bound organelle, consisting of proteinaceous polyhedral shells that encapsulate enzymes, protecting the contents from their surrounding milieu and/or the milieu from reactants in their interior. The self-assembling, 25-42 nm nanocompartment shell, unlike larger bacterial microcompartments, is made of only one protein, and has only a few proteins inside. Shells about vary from about 25-42 nm in diameter. The shell protein has an HK97-like fold and probably evolved from a viral protein. Artificial encapsulin nanocompartments can be expressed and filled with cargo proteins for biotechnological uses. They are found in many bacterial and a few archaeal phyla.
protein nanocompartment