Splits dipeptides with a prolyl or hydroxyprolyl residue in the C-terminal position. Plays an important role in collagen metabolism because the high level of iminoacids in collagen. Defects in PEPD are a cause of prolidase deficiency (PD). Prolidase deficiency is an autosomal recessive disorder associated with iminodipeptiduria. The clinical phenotype includes skin ulcers, mental retardation, recurrent infections, and a characteristic facies. These features, however are incompletely penetrant and highly variable in both age of onset and severity. There is a tight linkage between the polymorphisms of prolidase and the myotonic dystrophy trait. Belongs to the peptidase M24B family. Eukaryotic-type prolidase subfamily. 2 isoforms of the human protein are produced by alternative splicing. Note: This description may include information from UniProtKB.