Tripeptidyl Peptidase II (TPP2)

TPP2 encodes a mammalian peptidase that, at neutral pH, removes tripeptides from the N terminus of longer peptides. The protein has a specialized function that is essential for some MHC class I antigen presentation. The protein is a high molecular mass serine exopeptidase; the amino acid sequence surrounding the serine residue at the active site is similar to the peptidases of the subtilisin class rather than the trypsin class. tripeptidyl peptidase II, it is a high molecular mass serine exopeptidase, consisting of subunits with molecular mass 135,000. The amino acid sequence surrounding the serine residue at the active site is similar to the peptidases of the subtilisin class, whereas other mammalian serine peptidases are of the trypsin class. The enzyme has been purified from human erythrocytes.