Development of an assay for measuring proprotein-conversion activity on a multiplex magnetic bead-based array platform

Abstract

This chapter describes a protocol for measuring prolyl oligopeptidase (POP) activity using a biotinylated peptide substrate coupled to magnetic microspheres. The complex is incubated in the presence of a pituitary extract and activity can be detected by loss of the biotin label. The assay can be multiplexed for measuring multiple proprotein-cleaving enzymes simultaneously and can be used in analyses of neuropsychiatric diseases in which proteolytic cleavage of biologically active peptides is known to play a role.