title: Purification and properties of gamma-glutamyl transpeptidase from rat deciduoma.
abstract: gamma-Glutamyl transpeptidase has been purified by chromatographic methods from endometrium of rat deciduoma. The membrane-bound enzyme, digested with papain, eluted as a single fraction during chromatography and the final preparation had a specific activity of 104.5 U/mg protein. The molecular weight of the native enzyme was approximately 70,000 and the protein could be resolved into a heavy and a light fraction on sodium dodecyl sulfate-acrylamide gel electrophoresis with molecular weights of 45,000 and 23,000, respectively. The enzyme had a pH optimum of 8.2 and Km's for donor (p-nitroanilide) and acceptor (glycylglycine) were 1 and 7.6 mM, respectively. The enzyme was inhibited by L-serine in the presence of borate with a Ki of 22 microM. The decidual enzyme was not heat stable and its electrophoretic mobility was decreased after neuraminidase treatment.
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D000818:Animals; D002413:Cations, Divalent; D003656:Decidua / Q000201:enzymology*; D005260:Female; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008970:Molecular Weight; D011247:Pregnancy; D051381:Rats; D013347:Subcellular Fractions / Q000201:enzymology; D013379:Substrate Specificity; D013439:Sulfhydryl Reagents / Q000494:pharmacology; D005723:gamma-Glutamyltransferase / Q000302:isolation & purification* / Q000378:metabolism
chemical_list: D000596:Amino Acids; D002413:Cations, Divalent; D013439:Sulfhydryl Reagents; D005723:gamma-Glutamyltransferase