Quenched Fluorescent Substrate- Based Peptidase Assays

The use of specific quenched fluorescent substrates (QFS) provides a rapid and sensitive method to measure peptidase activity, and is readily adaptable to highthroughput screening of potential peptidase inhibitors. In this chapter, we discuss general considerations for the development of QFS assays, and describe in detail an assay protocol for the mammalian metallopeptidase, endothelin-converting enzyme.