Ubiquitin carboxyl-terminal hydrolases (UCH) () []are thiol proteases that recognise and hydrolyse the peptide bond at the C-terminal glycine of ubiquitin. These enzymes are involved in the processing of poly-ubiquitin precursors as well as that of ubiquinated proteins. The deubiquitinsing proteases can be split into 2 size ranges, 20-30kDa() and 100-200kDa []: the second class consist of large proteins (800 to 2000 residues) that belong to the peptidase family C19, and this group is currently represented by yeast UBP1 []. This entry includes the peptidase domain of ubiquitin-specific peptidase 38 (USP38; MEROPS identifier C19.056), which belongs to the second group of deubiquitinsing proteases. It has specificity for 'Lys-63'-linked ubiquitin chains [].
