title: Properties of an estrogen-induced hydrolytic enzyme from mouse uterus.
abstract: The purification and properties of an estradiol-sensitive hydrolytic activity from mouse uterus which fits several criteria for being an induced protein are described. The activity in the uteri of immature animals can be stimulated 2--4-fold by estradiol to that approaching the adult level. Stimulation is blocked by puromycin. The enzyme which we have designated hydrolase II, was purified approx. 400-fold to apparent homogeneity by chromatography on Affigel Blue, DEAE-cellulose and octyl-Sepharose. Hydrolase II is a single chain polypeptide with an estimated mol. wt = 65,000 daltons and has an N-terminal serine residue. A variety of N-blocked L-amino acid nitrophenyl esters are cleaved by the enzyme. Km's at pH 7.2 were all approx. 40 microns. Of substrates tested, phenylalanine nitrophenyl ester had the highest Vmax. Cbz-beta-alanine nitrophenyl ester, which is not a normal protease substrate was cleaved with a Km of 145 microM. The enzyme had no detectable activity against peptide nitroanilide substrates for trypsin-, chymotrypsin- or elastase-like enzymes. It is inhibited by ZPCK and DIFP but not by TLCK and Ala-Ala-Pro-Ala chloromethyl ketone, a potent inhibitor of elastase-like enzymes. Mouse plasma protein protease inhibitors were without effect as was SBTI. Our results rule out hydrolase II being a carnosinase, non-serine esterase, plasminogen activator, collagenase or collagenase activator and suggest that it is a chymotrypsin-like protease.
mesh_terms: D000818:Animals; D004790:Enzyme Induction; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D007527:Isoenzymes / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D007700:Kinetics; D051379:Mice; D010447:Peptide Hydrolases / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D013379:Substrate Specificity; D014599:Uterus / Q000201:enzymology*
chemical_list: D007527:Isoenzymes; D004958:Estradiol; D010447:Peptide Hydrolases