A mobile loop near the active site acts as a switch between the dual activities of a viral protease/deubiquitinase
The five molecules are displayed in surface representations for PRO/DUB wild type (top left) and molecules 'A' (middle) and 'B' (right) of ΔC5 (top) and I847A (bottom, in cyan and sky-blue, respectively), all in the same orientation. The C-terminus is indicated, and P866 and L820 are labeled in the WT. The hydrophobic zipper is in red (P866, P867) and orange (L781, L820). Residue 847 is in black.