Matrix metalloproteinases (MMP) are a family of zinc-dependent endopeptidases that degrade matrix proteins. MMPs include collagenases, gelatinases, matrilysins, enamelysins, metalloelastases, stromelysins and other structural protein and receptor lysins. The activity of these enzymes is selectively inhibited or measured by appropriately labeled peptides. MCA-Pro-Leu-Ala-Cys-MeOBzl-Trp-Ala-Arg-DNP-Dap-NH2 is used as a fluorogenic substrate for matrix metalloprotein-14 (Stomelysin, MMP-14).