substrate mocacplgla 2 pr dnp ar nh 2 fluorescence was measured with a photon technology international pti spectrofluorometer interfaced to a pentium computer equipped with the ratiomaster u2122 and felix u2122 hardware and software respectively the cuvette compartment was thermostated at 25 0 u00b0 c substrate hydrolysis was monitored at emission and excitation wavelengths of 328 and 393 nm and excitation and emission band passes of 1 and 3 nm respectively fluorescence measurements were taken every 4 s less than 10 hydrolysis of the fluorogenic substrate was monitored as described by knight knight c g methods enzymol 1995 248 18 34 stromelysin 1 enzymatic activity was monitored using the synthetic fluorogenic substrate mocacrpkpve nva wrk dnp nh 2 peptides international louisville ky at excitation and emission wavelengths of 325 and 393 nm and excitation and emission band passes of 1 and 3 nm respectively human pro mmp 2 pro mmp 9 timp 1 and timp 2 were expressed in hela s3 cells infected with the appropriate recombinant vaccinia viruses and were purified to homogeneity as previously described fridman r fuerst t r bird r e hoyhtya m oelkuct m kraus s komarek d liotta l a berman m l stetler stevenson w g j biol chem 1992 267 15398 15405 fridman r birs r e hoyhtya m oelkuct m komarek d liang c m berman m l liotta l.