Scientific Background | 520 MMP FRET Substrate 7, FAM/QXL520 is an internally quenched peptide designed for fluorescence-resonance-energy-transfer measurements of matrix metalloproteinase activity. The peptide combines an MMP-sensitive recognition sequence with the 5-FAM/QXL 520 reporter pair. In the intact molecule, QXL 520 suppresses 5-FAM fluorescence; proteolytic cleavage separates the reporter pair and restores green fluorescence near 494/521 nm. The verified LifeTein activity profile includes MMP-7, MMP-12 and MMP-13. MMPs participate in extracellular-matrix turnover and also process signaling proteins, receptors, cytokines and other bioactive molecules. |
Experimental Notes | This PYAYWMR sequence is a distinct recognition motif and should not be treated as interchangeable with PLGL-family substrates. MMP peptide substrates generally show overlapping enzyme specificity, so activity in complex samples should be assigned with purified enzymes, selective inhibitors, or orthogonal controls. Protect the FAM/QXL 520 reagent from light. |
