Post-proline cleaving enzyme. Purification of this endopeptidase by affinity chromatography

J Biol Chem. 1976 Dec 10;251(23):7593-9.


The endopeptidase, post-proline cleaving enzyme, has been purified 10,500-fold in an overall yield of 18% from lamb kidney. The enzyme possesses a specific activity of 45 mumol/mg/min as tested with the substrate Z-Gly-Pro-Leu-Gly (Km = 6.0 X 10(-5)), has a molecular weight of 115,000, is comprised of two subunits with a molecular weight of 57,000, and exhibits maximal activity at pH 7.5 to 8.0. With the exception of the -Pro-Pro linkage, the -Pro-X-peptide bond (X equals L- and D-amino acid residues) located internally in the peptide sequence can be hydrolyzed (cleavage occurs faster when X = lipophilic side chain as compared to X = acidic side chain). The appropriate -Pro-X- bonds in zinc-free porcine insulin, oxytocin, arginine vasopressin, angiotensin II, bradykinin-potentiating factor were cleaved. Human gastrin, adrenocorticotropic hormone, denatured guinea pig skin collagen, and ascaris cuticle collagen were not degraded. Dipeptides with the structure Z-Pro-LD-X competitively inhibit post-proline cleaving enzyme.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Chromatography, Affinity
  • Endopeptidases / isolation & purification*
  • Endopeptidases / metabolism
  • Hydrogen-Ion Concentration
  • Kidney / enzymology*
  • Kinetics
  • Proline
  • Prolyl Oligopeptidases
  • Serine Endopeptidases
  • Sheep
  • Structure-Activity Relationship


  • Proline
  • Endopeptidases
  • Serine Endopeptidases
  • PREPL protein, human
  • Prolyl Oligopeptidases