Dodecameric protein

A dodecameric protein has a quaternary structure consisting of 12 protein subunits in a complex. Dodecameric complexes can have a number of subunit 'topologies', but typically only a few of the theoretically possible subunit arrangements are observed in protein structures.

A dodecamer (protein) is a protein complex with 12 protein subunits.

A common subunit arrangement involves a tetrahedral distribution of subunit trimers (or 3-4-point symmetry). Another observed arrangement of subunits puts two rings of six subunits side by side along the sixfold axis (or 2-6-point symmetry).

Dodecameric proteins include

• Complete gap junction channel, composed of two hexamers.
• glutamine synthetase (PDB code: 2gls)
• Dodecameric ferritin (PDB code: 1qgh)
• Aβ42 - Amyloid-beta 42
• Helicobacter pylori urease

References

• The Protein Data Bank (PDB)
• Protein Interfaces, Surfaces and Assemblies Server (PISA) part of the PDBe.