Bacterial microcompartment

A bacterial microcompartment is a structure inside bacteria. They are made of a protein shell which surrounds and encloses various enzymes. They are similar to eukaryotic cell organelles, but do not have plasma membranes. They do not contain lipids.
These compartments are typically about 100-200 nanometres across and made of interlocking proteins.
Protein-enclosed compartments are also found in eukaryotes, such as enzyme encapsulation.