Detection of Protease Activity with a Fluorescence-labelled Peptide Substrate on a TLC Plate

Abstract

  A small amount of peptidase activity could be detected using an amine derivatizing reagent, fluorescein isothiocyanate (FITC), which has been used to produce a fluorogenic peptide. The substrate produced, FITC-peptide, gave a clear spot on a silica gel sheet upon exposure to UV light. The peptidase activity of angiotensin-converting enzyme (ACE), trypsin, chymotrypsin, cucumisin, and that of some plant tissues were detected by using a fluorogenic angiotensin I. This showed that the substrate specificity of proteolytic enzymes can be distinguished from the others by this procedure.