3DCOMPLEX

A Database for protein complexes of known 3-dimensional structure... In top-down hierarchy, complexes with different topologies are never grouped together. This can be problematic in respect of the redundancy because closely related complexes can have different topologies, as illustrated with two human hemoglobin β4 homotetramers above. Therefore, in addition to the top-down hierarchy we provide a bottom-up hierarchy, where these two complexes are grouped together. The bottom-up hierarchy is identical to the top-down, except for homo-oligomers, which are grouped together on the basis of their symmetry instead of their topology. If you intend to carry out an analysis on homomers, we recommend the use of the bottom-up hierarchy.