title: An alkaline metallo-proteinase in the human uterine cervix an changes in its activity by cervical ripening.
abstract: Human uterine cervix at term pregnancy was found to contain an alkaline metallo-proteinase by use of a synthetic substrate, 2,4-dinitrophenyl-L-Pro-L-Gln-Gly-L-Ile-L-Ala-Gly-L-Gln-D-Arg. The enzyme (with a molecular weight of 3.8 . 10(4)) was most active around pH 9.2 toward casein and N alpha-benzoyl-DL-Arg-rho-nitroanilide. [14C]-Gelatin and proteoglycan subunit were also substrates for the enzyme, but [14C]collagen was not. In particular, the enzyme digested gelatin 70-times faster than the novel neutral proteinase in the cervix. Although EDTA was a potent inhibitor, 1,10-phenanthroline, human serum, diisopropylfluorophosphate and elastatinal had no effect on the enzyme. Alkaline proteinase in term pregnant cervices was significantly higher than in non-pregnant ones.
mesh_terms: D001586:Benzoylarginine Nitroanilide / Q000378:metabolism; D002364:Caseins / Q000378:metabolism; D002584:Cervix Uteri / Q000201:enzymology* / Q000502:physiology; D004140:Dinitrophenols; D010450:Endopeptidases / Q000302:isolation & purification / Q000378:metabolism*; D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007743:Labor, Obstetric; D008666:Metalloendopeptidases; D009842:Oligopeptides / Q000378:metabolism; D011247:Pregnancy; D011480:Protease Inhibitors; D013379:Substrate Specificity
chemical_list: D002364:Caseins; D004140:Dinitrophenols; D009842:Oligopeptides; D011480:Protease Inhibitors; C024118:DNP-peptide; D001586:Benzoylarginine Nitroanilide; D010450:Endopeptidases; D008666:Metalloendopeptidases