Abstract
Glutamate dehydrogenase (GDH) of S. fallax was purified 2000-fold to apparent homogeneity. As estimated by gel filtration and SDS-PAGE, a native molecular weight of M r 210 000 and a subunit molecular weight of M r 52 000 were determined, indicating that the enzyme is tetrameric with subunits of identical molecular weights. Isoforms could not be detected. Purified GDH displayed pH-optima of 8.6 with NAD(P)H and 7.7 with NAD + and a high K m for ammonium of 28 and 41 mM with NADH and NADPH as coenzymes, respectively. The enzyme is located in the mitochondria. The occurrence of GDH activity in the cytosolic fraction was addressed to organelle breakage. Enhanced ammonium concentrations and a reduced carbon supply caused a substantial increase in GDH activity. Labelling studies with [ 15N]ammonium and [ 15N]glutamate were consistent with the role of the enzyme in the oxidative deamination of glutamate. © 1997 Elsevier Science Ltd. All rights reserved
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
