English: Semi-schematic of the proteasome (PDB accession code 1G0U). The alpha subunits of the two outer rings are shown in green as 5 Angstrom spheres centered on the subunit centroid, which coincides with the CB atom of Leu137. The beta subunits of the two inner rings are shown as ribbon diagrams of different colors. The CA atoms of residue 1 of the beta subunits (corresponding to the catalytic residues) are likewise shown as 5 Angstrom spheres of the same color as their ribbon. The beta subunits of 1G0U corresponding to chain H, M, N, 1 and 2 have been removed to produce a "cutaway" effect; thus, there are five subunits in the lower beta ring and four in the upper. The sphere size was set using the "set sphere_scale=X" command in PyMol. Made by me on 5 January 2007 using PyMol; the cutaway PDB file was made by hand editing. Hereby released under the GFDL.