Some enzymatic properties of NAD +-dependent glutamate dehydrogenase of mussel hepatopancreas ( Mytilus edulis L.)—requirement of ADP

• Published in: Comparative biochemistry and physiology. B, Comparative biochemistry Vol. 82; no. 1; pp. 197 - 202
• Main Authors: Ruiz Ruano, A., Allende Riaño, J.L., Ruiz Amil, M., Herranz Santos, M.J.
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 1985; Elsevier Science
• Subjects: Biological and medical sciences; Fundamental and applied biological sciences. Psychology; Invertebrates; Mollusca; Physiology. Development; Marine environment; Bivalvia; Enzyme; Hepatopancreas; Kinetics; Invertebrata; Mollusca; Physicochemical properties
• ISSN: 0305-0491
• DOI: 10.1016/0305-0491(85)90152-X

1. 1. The glutamate dehydrogenase of mussel hepatopancreas is NAD(H) dependent and shows absolute requirement for ADP as cofactor. 2. 2. The optimum pH for GDH lies between 7.4 and 8.2 (reductive amination) and 9.5 (oxidative deamination). The enzyme has an activation energy of 53.9 kJ/mol and an average Q 10 of 1.65. 3. 3. ADP and 2-oxoglutarate stabilize the enzyme, while NADH diminishes the stabilization significantly. 4. 4. In the sense of reductive amination the apparent K m values are 0.38 mM for 2-oxoglutarate, 34 μM for NADH and 20 mM for NH 4 +. In the opposite sense the apparent K m for glutamate is 5 mM and 0.55 mM for NAD +.