Anti-trypsin like peroxisomal matrix peptidase 1 antibodies are used for the immunodetection of the protein encoded by the TYSND1 gene. In humans, the canonical protein has a reported length of 566 amino acid residues and a mass of 59.3 kDa. Its subcellular localization is in the peroxisomes. Alternative splicing is reported to yield 2 different isoforms for this protein. A member of the Peptidase S1B protein family, it is reported to be a peroxisomal protease that mediates both the removal of the leader peptide from proteins containing a PTS2 target sequence and processes several PTS1-containing proteins. Post-translational modifications have been described, including protein cleavage. Other names for this target antigen include peroxisomal cysteine endopeptidase, peroxisomal matrix protein-processing protease, peroxisome leader peptide-processing protease, and peroxisomal leader peptide-processing protease. Gene orthologs have been identified in the mouse, rat, bovine, frog, zebrafish, chimpanzee and chicken species.