Structure of human ubiquitin-specific protease 7 (HAUSP) covalently bound to ubiquitin aldehyde. The architecture of this enzyme around the catalytic site closely resembles that of other proteases of the papain clan. The catalytic site consists of a triad of residues in a charge relay system*, from Asp481 to His464 to Cys223. In other members of the C19 family, the role of the aspartate can be played by an asparagine or even a serine.
Notably, the proper alignment of the catalytic triad in this enzyme depends on its interaction with ubiquitin (shown in pink). Thus, in the structure of the isolated protease, the distance between the Cys and His residues is at least 9.7 Å.
*See family C26 for a more detailed explanation of the charge relay system in a catalytic triad.



  • Structures are rendered as ribbons. Catalytic and catalytic metal-complexing residues are shown as neons. Inhibitors are displayed as space filling spheres.

  • Carbons are shown in light gray, hydrogens in cyan, oxygens in red, nitrogens in blue, and sulfurs in yellow.

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