Prolyl Oligopeptidase, also known as prolyl endopeptidase and post-proline cleaving enzyme, is a serine peptidase displaying specificity for the cleavage of Pro-Xaa bonds of oligopeptide substrates (1, 2). The peptidase is known to hydrolyze a variety of biologically active peptides such as bradykinin, substance P, neurotensin, and vasopressin (3). Because of its action on neuropeptides, Prolyl Oligopeptidase is considered to be involved in processes such as learning, memory, and depression (4). Recombinant protein corresponding to Leu2-Gln710 from mouse Prolyl Oligopeptidase/PREP, N-terminal Met, and 6-His tag, expressed in Spodoptera frugiperda, Sf 21 (baculovirus). Molecular Weight: ~82kD Biological Activity: Measured by its ability to convert the substrate benzyloxycarbonyl-Gly-Pro-7-amido-4-methylcoumarin (Z-GP-AMC) to Z-Gly-Pro and 7-amino-4methylcoumarin (AMC). The specific activity is > 4,500 pmoles/min/ug, as measured under the described conditions. Storage and Stability: May be stored at 4C for short-term only. Aliquot to avoid repeated freezing and thawing.. Store at -20C. Aliquots are stable for 6 months after receipt at -20C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.