Purification and characterization of a novel glutamyl aminopeptidase from chicken meat

• Published in: Meat science Vol. 64; no. 2; pp. 163 - 168
• Main Authors: Maehashi, Kenji, Abe, Takako, Yasuhara, Tadasu, Yamasato, Kazuhide, Yamamoto, Yasushi, Udaka, Shigezo
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01-06-2003; Elsevier
• Subjects: Analytical, structural and metabolic biochemistry; Biological and medical sciences; Chicken; Enzymes and enzyme inhibitors; Fundamental and applied biological sciences. Psychology; Glutamic acid; Glutamyl aminopeptidase; Hydrolases; Meat; Umami; Glutamic acid; Chicken; Glutamyl aminopeptidase; Umami; Meat; Purification; Enzyme; Aminopeptidases; Meat: Glutamic acid; Meat product; Chicken meat; Characterization; Peptidases; Hydrolases; Molecular mass
• ISSN: 0309-1740; 1873-4138
• DOI: 10.1016/S0309-1740(02)00175-4

A novel glutamyl aminopeptidase (aminopeptidase A, EC 3.4.11.7) was purified from chicken meat by ammonium sulfate fractionation, ethanol fractionation, heat treatment, and successive column chromatographies of DEAE-Sepharose CL-6B and Sephadex G-200. The purified enzyme migrated as a single band on SDS-PAGE. The molecular weight of this enzyme was found to be 55,000 and 550,000 by SDS-PAGE and Sephadex G-200 column chromatographies, respectively. This enzyme hydrolyzed Glu- and Asp-, but not Leu-, Arg-, and Ala-2-naphthylamide (-2NA) at all. The optimum pH and temperature for hydrolysis of Glu-2NA was 7.5. and 70°C, respectively. Reducing agents such as cysteine and dithiothreitol inhibited the activity of this enzyme at concentrations of 1 mM. However, the activation by Ca
2+ and the inhibition by amastatin were not observed.